Array

Array:-array is a set of similar data type element we can store more than one elements and array simultaneously and array is also called subscript variable array are similar to matrices using common variable and single variable.

In other words an array is a group or a table of values referred to by the same variable name array element is also a variable in the array declaration one must define the type of the array.

The type of array:-

1. one dimensional array

2. multi dimensional array

int a [5]

data type of array name maximum

element permitted size

in general one dimensional array may be expressed as:-

Data type array name[]

Eg:

int marks[300]

int mark [0]

int l mark[0.002] not valid

int mark[-90]

array initialization:-

general format:-

data type array name[expression]

={element1,ele2,ele3};

int value [7]={10,11,5,13,16,18,19};

or index

value [0]=10 int value [7]

value [1]=11

| |

value [6]=19

10 11 5 13 16 18 19

Note:- array index starts for 0 to n-1 where n is the maximum size of the array. If the array element are not assigned explicitly, initial value will be automatically set to zero.

Eg1

int no[5]={1,2,3}

no[0]=1

no[1]=2

no[2]=3

no[3]=0

no[4]=0

eg2- NOTE : Please Ignore Human being typing mistakes

int a[7]={1,2,3,4,5,6,7}

int i;

printf(“\n contents of the array”);

for (i=0;i<=6;i++)

{

printf (“%d\n”,a[i]);

}

Note:-

a[0],a[1],a[2],a[3],a[4]

these are indices/subscript

eg3

int a[10],i; \\ int declaration

printf(“enter ten values”);

for(i=0;i<=a;i++)

{ scanf(“%d”,&a[i]); \\ by keyboard

}

for(i=0;i<=a;i++)

{

printf(“my array value \n”);

printf(“%d”,a[i]);

}

Explanation:- ex. no(suppose)

a[0]=101; a[1]=102;

a[2]=202; a[3]=1001;

Program:-

void main()

{

int x[3];

x[0]=5; ⁰

x[1]=15;

x[2]=x[0]+x[1];

printf(“%d”,x[2]);

}

Program:

for(i=0;i<=4;i++)

{

x[i]= i++;

for{i=0;i<=4;i++)

{

printf(“%d \n”,x[i]);

}

Multi dimensional array:-

M.D. array are define in the same manner as one dimensional arrays except that a separate pair of square brackets are required for each subscript thus a 2-d array will require two pairs of squares brackets 3-d array will require the pairs of square brackets and so on.

Format:- Data type array name[exp1] [exp2] [exp3]

Initialization:-

2-d array provides us matrix form in form of rows and columns we use the separate square bracket for define M.d. array

int a[2] [2]

rows columns

frist bracket for row & second bracket for columns

inilization:-

int a[3][2]={{70,80}{30,40}{63,92}};

int b[2][3]={{10,20,30}{16,18,30}};

int a[4][3]={{70,10,80}{16,80,90}{63,18,70}{17,10,40}};

output:-

Character array:-

Character-datatype array name[exp]

Eg.

char page[40];

char color[3]=”red”;

color[0]=”r”;

color[1]=”e”;

color[2]=”d”;

1. character array always terminates (end) with (‘\o’) (null) (null character)

r e d ‘\o’

Null char

Eg.

char line[]=“this is a my program”;

2. this null character will be added automatically by the compiler provided there is enough space to accommodate the char

int i

char name [ ]=”Ram lal Prasad babu”;

printf(“content of array”);

for(i=0;name[i]!=”\o”;i++)

{

printf(“%d /n”,name[i]);

}

R A M L A L P R A S A D

0 1 2 3 4 5 6 7 8 9 10 11 12 13

One dimensional array:-

A list of items can be given one variable name using one subscript & such a variable is called a single subscript variable or a one dimensional array

The subscript can begin with no 0.That is x[0] is allowed.

If we want to represent a set of five no.say (35,40,20,57,19)( by an array variable no then we may declare the variable no as follows:

int number[5];

and the value of an array element can show as follows:

x[0]=35 x[1]=40 x[2]=20 x[3]=57 x[4]=19

Declaration of 1-d array:-

float hight[50];

declares the hight to be an array containing 50 real elements similarly int group[10]; declares the groups as an array contain 10 integer values

when we declaring char array we must always allow one extra element space for the null terminator

declaration must end with semi-colon(;)

.Two dimensional array:-

Declaring two –d array is similar to declaring one-d array there will be an extra set of [] to indicate the second index thus a 2-d array can be defined as

Eg.

int array [4][4];

initializing of 2-d array:-

like one-d array 2-d array may be initialized by following

static int table[2][3]={0,0,0,1,1,1};

row columns

this can be also written as: static int table[2][3] =[{0,0,0},{1,1,1}];

Standard library string functions or arithmetic operations:-

#include <string.h>

Function use

1. strlen() find the lenth of the string

2. strlwr() convert the string to the lower case

3. strupr() convert the string to the upper case

4. strcat() append

5. strcpy() copies a string one in to anther

6. strcmp() compiler a string one in to anther

7. strrev() reverse a string one in to anther

8. strchar() find frist occurance

Find the Errors & output and also try to complete the program.

program:-

1. char arr[ ] =”xyz”;

int len;

int lwr,upr,rev;

len = strlen (arr);

printf(“%d”,len);

lwrstr (arr);

uprstr (arr);

revstr (arr);

2. char source [ ]=”language”;

char target [20]:

str cpy (target, source);

printf(“%s”,source);

printf(“%s”, target);

3. char source[ ]=”hello”;

char target[30]=”good morning”;

strcat(target, source);

printf(“%s”,target);

result:-hello good morning

4. char string1[ ]=”hello”;

char string2[ ]=”h”;

int i,j,k;

i=strcmp(string1”hello”);

j=strcmp(string1,string2);

k=strcmp(string1,”hello xyz”);

printf(“%d\n%d\n%d\n”,i,j,k);

Program :- matrix{entering 2*2 matrix data}

int [2] [2],i,j;

for(i=0;i<=1;i++)

{

for(j=0;j<=1;j++)

{

printf(“enter a number of matrix”);

scanf(“%d”, &x[i] [j]);

}

Explanation:-

x[0] [0]=2

x[0] [1]=2

x[1] [0]=2

x[1] [1]=2

/*displaying 2*2 matrix data*/

int s=0;

int[2] [2] ,i,j;

for(i=0;i<=1;i++)

{

for(j=0;j<=1;j++)

{

printf(“sum of matrix elements”);

s=s+x[i] [j];

printf(“%d”,s);

}

Program:-

main()

{

int num [ ]={24,34,12,44,56,17};

int i;

for(i=0;i<=5;i++)

{

printf(“\n address=% ”,num [i]);

printf(“element=%d”,num [i]);

}

Output:-

Address = 100 element =24

” = 102 ” =34

” = 104 ” =12

” = 106 ” =44

” = 108 ” =56

” = 110 ” =17

Summary:-

Note:-1. all element of the array must be same data type in this sensor it is homogenous data structure

Note:-2. the allocation information about an array is fixed at compiler time

Note:-3 during execution the memory space is allocated for array. For all the element of array continuous space is allocated. The array name is the start address of this memory.

Note:-4.

Normally declaration

#define max 100

int main()

{

int a[max];

------------

-----------

}

Eg.

int arr[2][3]={12,10,16,18,20,22};

int arr[ ] [ ]={12,10,16,18,20,22};

int arr[2] [ ]={12,10,16,18,20,22};

int arr [ ][ ]={12,10,16,18,20,22}; // check is it valid or not

3-D array:-

int arr[3][4][2]={{{2,4},{7,8},{3,9},{5,6}}, {{7,6},{3,4},{5,3},{2,3}},{{7,6},{3,4},{8,9},{5,3}}};

A three D array can be as a arrays of the outer array has three element of which is a 2 D array of 4 * 2 D array.

Que:-How to store 3D array in memory?

Que:-How to store 2D array in memory?

Program-:

Addition of two matrix

int x[3][3] ,y[3][3] ,z[3][3];

int i,j,k;

for (i=0;i<=2;i++)

{

for(j=0;j<=2;j++)

{

printf (“Ist matrix”);

printf (“enter the no”);

scanf (“%d”,&x[i][j]);

}

for (i=0;i<=2;i++)

{

for(j=0;j<=2;j++)

{

printf (“II^nd matrix”);

printf (“enter the no”);

scanf (“%d”,& y[i][j]);

}

for (i=0;i<=2;i++)

{

for(j=0;j<=2;j++)

{

z[i][j]=x[i][j]+y[i][j]

printf(“%d”, z[i][j]);

}getch();

}

Program-: Find the Errors & output and also try to complete the program.

Find out the maximum & smallest number with the help of array

for (i=0;i<=9;i++)

{

printf (“enter the ten no”);

scanf (“%d”,&x[i]);

}

for(j=0;j<=i;j++)

{

if (x[j]=x[i])

{

printf (“same number”)

i--;

break;

}

max=x[0];

for(i=0;i<=9;i++)

{

if (max<x[i]

{

max=x[i];

}

printf(“%d”,max);

}

getch();

}

Q.Write a program to occurrence of an element in the array or find out the location of desired Element in the given array ?

/*W A P to find squar of any no*/

/* W A P to find the power of 2ⁿ*/ Hint for(i=1;i<=10;i++) power(2,i)

/*W A P to find the ascending and descending the element if the array*/

Sorting

int a[5],t,i,j,temp;

printf(“enter the size of array”);

scanf(“%d”,&t);

printf(“enter the value”);

for(i=0;i<t;i++)

{

scanf(“%d”,&a[i]);

}

for(i=0;i<t;i++)

{

for(j=i+1;j<t;j++)

{

if(a[i]>a[j])

{

temp=a[j];

a[j]=a[i];

a[i]=temp;

}

for(i=0;i<t;i++)

{

printf(“descending order%d”,a[i]);

}

String :-

String are array of char type if we want to store sequence of char like a word or a sentence we can use string type variable in our program last of string array null char store (“\0”)but in case of integer array no null char store at the last location

char x[10]=”DEEPAK”;

gets( ) or puts( ):-

gets( ) is use for entering the string from the keyboard.it is similar to scanf( ) but major difference between space problem. in case of gets( ) we can pass one variable into gets( )

char s[10]

gets(s)

scanf(“%d”,&s);

gets(s);

puts( ):-

Puts can display only one string at same time.it is similar to printf( )but In case of puts(s) we can print only a value of variable we can not print a msg by using puts(s).which is possible in printf( ) only using printf( ) we can print msg as well as value of both.but in case of puts(s)we can print one string at a time

Eg Puts(s);

Puts(“hello”);

Program

main()

{

char name[25];

printf(“enter your name”);

scanf(“%s”,name);

printf(“%s”,name);

}

Test this program using different type of string

char name[25];

printf(“enter your full name”);

gets(name);

puts(“hello”);

puts(name);

2-d char array:-

Eg main()

{

char list [7] [10] =

{

“shilpi”

“upasana”

“rena”

“neeti”

“Deepak”

“amita”

“Anand”

}
}

Program-:

#include<stdio.h>

#include<conio.h>

main()

{

char name[]=”krishna”

int i=0;

while(i<=6)

{

printf(“%c”,name[i]);

i++ ;

}

Output:-

K r i s h n a

Program

#include<stdio.h>

#include<conio.h>

main()

{

char name[]=”krishna”

int i=0;

while(name[i]!=’\0’)

{

printf(“%c”,name[i]);

i++ ;

}

output:-

0 –K Memory location

1- r

2- i

3-s

4-h

5-n

6-a

Program

#include<stdio.h>

#include<conio.h>

main()

{

char name[]=”krishna”

printf (“%s”, name);

}

/* Find out the length of string*/

#include<stdio.h>

#include<conio.h>

main()

{

char name[]=”Hello”

int i=0;

while(x[i]!=’\0’)

{

i++;

}

printf(“%d”,i);

}

/*Power Program*/

Find the Errors & output and also try to complete the program.

Sorting:-

There are three types of sorting:-

1. Selection sort

2.Bubble sort

3.Insertion sort

Selection Sort:-

#include<stdio.h>

#include<conio.h>

main()

{

int x[5]={5,10,15,2.19}

int i,j,t;

for(i=0;i<5;i++)

{

for(j=1+i;j<5;j++)

{

if(x[i]>x[j])

{

t=x[i];

x[i]=x[j];

x[j]=t;

}

for(i=0;i<5;i++)

{

printf (“%d”,x[i]);

}

Output:-

int x[t]={2,5,10,15,19}

Bubble Sort:-

#include<stdio.h>

#include<conio.h>

main ()

{

int i,j,t;

for(i=0;i<5:i++)

{

for(j=0;j<4-i;j++)

{

if(x[i]>x[j+1])

{

t=x[j];

x[i]=x[j+1];

x[j+1]=t;

}

for(i=0;i<5;i++)

{

printf(“%d”,x[i]);

}

Insertion sort:-

#include<stdio.h>

#include<conio.h>

void main()

{

int x[5]={5,10,12,19,15};

int I,j,t;

{

printf(“%d”,x[i]);

}

for(i=0;i<5;i++)

{

for(j=i;j<5;j++)

{

if x[i]<x[j-1]

{

t=x[j=1];

x[j-1]=x[j];

x[j]=t;

}

/*concalenation and appending*/

Add two string in third array

void main()

{

char x[10],y[10],z[20];

int i=0j=0k=0;

printf(“enter the frist string”);

gets(x);

printf(“enter the second string”);

gets(y);

while(x[i]!=null)

{

z[k]=x[i];

k++;

i++;

}

z[k]=“ ”;

k++;

while(y[j]!=null)

{

z[k]=y[j];

k++;

j++;

}z[k]=null or ‘ ’;

printf(“%s”,z);

for(k=0;k[z]!=null;k++)

{

p rintf(“%c”,z[k]);

}

/*W A P to input string and check palindrome or not*/ Ex -KANAK

char x[20],y[20];

int i=0,j=0;

printf(“enter the string”);

gets(x);

while(x[i]!=null)

{

i++

}

for(j=i-1;j>=0;j--)

{

y[j]=x[i];

j++;

}

y[j]=null;

for(i=0;x[i]!=null;i++)

{

if(x[i]!=y[j])

{

printf(“not same character”);

break;

}

if(x[i]= =y[i])

{

printf(“same character”);

}

getch();

}

Program:-

char x[10];

char y[10];

char z[20];

int i=0,j=0,k=0;

strcat(x,y,z);

/*palindrome------- String*/

#include<string.h>

char x[20],y[20];int n;

printf(“enter the string”);

gets(x);

strcpy(x,y);

strrev(y);

n= strcmp(x,y);

if(n==0)

{printf (“palandrum”);

}else

printf (“not paladrum”);

/*copy one string to another*/

main()

{

char str 1 [80],str2[80];

int i;

prinf(“enter frist string”);

scanf (“%s”,str1);

for(i=0;str1[i]!=’\0’;i++)

{

str2[i]=str1[i];

str2[i]=’\0’;

printf (“%s\n”,str2);

printf (“no of character=%d\n”,i);

}

/*counting character words and lines in a text*/

#include<string.h>

main()

{

char line[81],ctr;

int i,c;

end =0;

character =0;

words=0;

lines =0;

printf(“key infu text”);

print(“give one space after each words\n”);

printf(“when completed press ‘return’\n \n”);

while(end= =0)

{

c=0;

while(ctr=getchar()!=’\n’)

line[c++]ctr;

line[c]=’\0’;

if (line[0]==’\0’)

break;

else

{

words++;
}

for(i=0;line[i]!=’\0’;i++)

if(line[i]== ‘ ’||line[i]==’\t’ );

words++;

}

/*counting lines and char*/

lines=lines+1;

character =character + str len (line);

{

printf(“%”,line);

printf(“%”,character);

printf(“%”,words);

}

Declaring and initializing string variable:-

The genral form of declaration o fstring variable Char string_name[size];

The size determine the no of char in the string name some eg are:-

Char city [10];

Char name[30];

When the compiler assign the char string to a array it automatically supplides a null char(‘\0’)at the end of string char city[10]= “london”;

String char city[20]=“new york”;

string char city[20]=“{’n’,’e’,’w’,’y’,’o’,’r’,’k’}”;

c also permits us to initialize z char array without declaring the no of char elements for eg:-

static char string [ ]={‘g’,’o’,’o’,’d’,’\o’};

reading string from terminal:-

char add [20];

scanf(“%s”,add);

gets(add);

writing string to screen:-

For printing a string statement we use %s format to print string to screen

we have use printf function with %s format to printf string to the screen

printf(“%s”,name);

getch( ):-

This function manily for reads a character from the key-board getch( ) is also used in tast of any program, here it is used for halt the screen.

-------------------------------------------------------------------------------------------------

Functions-:

Definition of function:-

Function is a sub program which can be called anywhere in our program when it is needsd

A function is self contain block of statements that perform a some specific kind of task

If we want to perform same task with different values that time we can use function if we talk about the main function ( ) its calling its self function may or may not be return any value. Function may cover program east to understand and provide reusability but spend some more time to groups the concept of calling a function.

Type of function:-function has two types:

1. built in function or library function

2. user defined function.

builtin function:-

builtin function are those function which are already built in library files

for eg:-

#include<math.h>

There are so many function in this file like power ( ),sin( ),sqrt( )

user define function:-

user define function are those functions which made by programmer. That means programmer can creat own function.

for eg:-

ABC( )

int add()

int AB()

the form of c function:-

function name (argument list)

argument declaration;

{

local variable declaration;

excutable statement1;

excutable statement2;

excutable statement3;

--------------------------

return(expression);

}

Eg:-

void abc();

int i;for (i=1i<=10;i++)

{

printf(“\n %d”,i);

}

void main()

{

printf(“hello”);

abc();

printf(welcome”);

abc();

printf(“very good morning to all of u”);

abc( );

}

/*program/

int xyz ( )

{

return(10);

}

void main( )

{

int a;

a=xyz();

printf(“%d”,a);

}

Output:- 10

/*program*/

int abc(int x)

{

return(x*5);

}

void main()

{

int a;

a=abc(10);

printf(“%d”,a);

}

Output:-50

/* program for addition*/

int add (int x, int y)

{

return (x+y);

}

void main()

{

int a;

a=add(50, 60);

printf(“%d”,a);

b=add(10, 20);

printf(“%d”,b);

}

output:-110 &30

/*square program*/

main()

{

float a,b,c;

printf(“\n enter any number”);

scanf(%”f”,&a);

b=squar(a);

printf(“\n square of %f is %f”,a,b);

}

square(float x);

{

float y;

y=x*x;

return(y);

}

output:- enter any no. 2

square of 2 is 4.000000

Note:-Need for user defined function:-

The program may become too large and complex and as a result the task of debugging , testing and maintaining become difficult if a program is divided into functional parts each parts may be indenpendelty coded and letter combine into a single unit. These sub program are called functions much easier to understand debug and test

Advantage:-

top down modular programming
length of source program reduced
easy to maintain
function may be use by many other programs

describe all these points

Note:-

The main difference between library function & user define function is that library function are not required to be written by us where as a user define function has to be developed by the user define function can later become a part of the c program library

modular programming:-

A large program is divided into small modules the c provides the modularization facilities of function which supports the modular programming modularization is a design time activity to take full advantage of modulation , modules should be independent of another

advantage of modular programming:-

simplicity is development:-
faster development:
reusability:-
abstraction:- it means hiding of details it provides simplicity
reduse code size:-
simplicity in testing and modification:

disadvantages of modular programming:

use of function increase the execution time:-

/* prototype */

int add (int x,int y);

int main()

{

int a,b,c;

a=10;

b=20;

c=add(a,b);

return 0;

}

int add (int x, int y);

{

int x ;

z=x+y;

return z;

printf(“%d”,z);

}

Note:- prototype mean behavior of function i. e. the return type the name the no & type of inpute parameter there is no need of identifiers in the prototype so the following is also sufficient

int add (int ,int);

this prototype is also called declaration or header the body of a function that contains actual code for the function is called definition the definition of can also be given before main() in this case there is no need of prototype

the function main() is calling function add( ) is called “called “ in the calling function there is a function called argument list in the head of called function the list in side the parentheses is called parameter list the type and no of argument list must exactly match with those of parameter.

The value of argument is assign to corresponding parameter.

c=add(a,b); /*calling*/

int add (int x,int y) /*header of definition*/

x=a assign value

y=b

The identifier a,b and c are called local identifiers of function main the identifiers x,y and z are called local identifiers or add function. A local identifiers can be used with in the function in which it is declared a,b and c are execible with main() only similary x,y and z are execible with in add ( ) only

The function can contain more than one return statement physically but logically only one will be executed out of them.

The return value can be discorded if not required if the function does not return any thisg its return type is void a void( )may or may have not return statement it shows the end of function we can return only single value from the function.

Multipli return values can be done with the help of structure.

Note:- The operating system maintain a user stack to keep track of functions called when a function is called a new entey of the of stack when the function end the entry is poped (to remove)

add( )

Stack (last in fast out)

/* find a factorial no using functions*/

long factorial (int);

int main( )

{

int n;

longfact;

printf(“enter a no”);

scanf(“%d”,&n);

fact=factorial(n);

printf(“\n the factorial is %d”, fact);

return 0;

}

long factorial (int num)

{

long fact =1;

for (int i=2;i<=num;i++)

fact*=i;

return fact;

}

/*program for making accept two no as parameter and return h.c.f*/

(Highest common factor)

int hcf(int x,int y);

int main()

{

int a,b,result;

printf(“\n enter two number”);

scanf(“%d%d”,&a,&b);

result=hcf(a,b);

printf(“\nthe hcf is %d ”,result);

return 0;

}

int hcf (int x, int y)

{

int result ,smaller;

smaller =(x<y)?x:y;

for (result = smaller; result>=1;result--)

{

if (x%result = =0)&& (y%result == 0)

return result;

}

/* program to print the given no is even or odd with using function */

#include<stdio.h>

#include<conio.h>

void main( )

{

clrscr ( );

int s(int);

int a;

printf(“enter any number for finding even or odd with the help of function concept \n”);

scanf(“%d”,& a);

s(a);

getch( );

}

s(int a);

{

if (a%2==0)

printf(“enterd no is even”);

else

printf(“entered no is odd”);

}

Note :-

A function is called it self such a process is called recursion.

Library function eg:- printf( )and scanf( )

User define function:-add( ) and swap( )

Writing function avoids rewriting the same code over and over using functions it becomes easier to write programs and keep track of what they are doing

Eg:-

func();

{

char ch;

printf(“\n enter any alphabet”);

scanf(%c”,&ch);

if (ch>=65 && ch<=90)

return(ch);

else

return(ch+32);

}

/*scope rule of function (local and global variable) */

main( )

{

int a=80;value (a);

printf(“\n%d”,a);

}

value (int b);

{

int b=60;

printf(“\n%d”,b);

}

Output :-

main( )

{

int i=20;

display (i);

}

display (int y);

{

int k=35;

printf(“\n %d”,j);

printf(“\n%d”,k);

Output:-

Advance feature of functions:-

function declaration and prototypes
calling function by value
calling function by reference (address)
recursion

pass(call) by value:-

in the formal parameter is changed it will not effect the actual parameter but in the case off pass by refrence if the formal parameter is changed the actual parameter will also changed

we can pass the value of array to a function we can pass the value of array to a function we can pass the address of a variable as an argument to a function ih the normal way.

We called a function and passed something to it we have always pass the value of variable to called function . such function calls are called by value.

Eg:-

void abc(int * x)

{

*x=*x+10;

printf(“%d”,*x);

}

void main( )

{

int a=50;

abc (&a);

printf(“%d”,a);

}

Output :-

/* pass by value*/

void swap (int a,int b)

{int t;

t=a;

a=b;

b=t;

printf(“%d%d”,a,b);

}

void main()

{ int x=10,y=20;

swap (x, y);

printf(“%d%d”,x,y);

}

Output:-

20,10

10,20

/* pass by reference*/

void swap (int *a,int *b)

{

int t;

t=*a;

*a=*b;

*b=t;

printf(“%d%d”,*a,*b);

}

void main( )

{

int x=10;y=20;

swap(&x , &y);

printf(“%d%d”,x,y);

}

Output::-

20,10

10,20

Note:-

The process of calling a function using pointers to pass the assess of

Variable is knows as call by reference The function which is called by reference changed the value of the variable used in the call

Why we use function?

There are two reasons to use function:-

writing functions avoids rewriting the same code over and over
using functions it becomes easier to write program and keep track of they are doing

Note:-

argument list

quadratic(a,b,c);

power(x,n);

square (y);

copy (name1,name2);

return value and their type:-

return 0;

return(expression);

return(x*y);

return(1);

return(0);

calling a function:-

p=mul(10,5)

Handling non-integer function:-

c-functions returns a value of type int as the default case when no other type is specified explicitly

eg:-

main()

{

float a,b,mul( );

double dir ( );

a=12.345;

b=9.82;

printf(“%f\n”,mul (a,b));

printf(“%f\n”,dir(a,b));

}

float mul (x, y);

float x,y;

{

return(x*y);

}

double dir(p, q);

double p, q;

{

return(p/q);

}

/*function with array */

Like the value of simple variable it is also possible to pass the value of an arrayto a function

void fa( )

{

int a[5], i;

printf(“enter the no”);

for(i=0;i<5;i++)

{

scanf(“%d”,&a[i]);

}}

void fadisplay( )

{

int i;

for( i=0;i<5;i++)

{

printf(“%d”,a[i];

}

void main( )

{

fa( );

fadisplay( );

}

Recursion:-

main( )

{

printf(“this is an eg of recursion\n”);

main( );

It is possible for the functions to call them selves. A function is call recursive if a statement with in the body of function calls the same function some times called circular definition recursion is the process of defining something interms of it self.

A function which called itself is called recursive function.

Program:-

int x=1;

void main( )

{

static int x=1;

printf(“hello”);

x++;

If (x<=10)

{

main( );

}

/*factorial program */

int fact(int x);

{

if (a==1)

{

return(1);

}

else{

return(a*fact (a-1));

}

void main( )

{

int n,x;;

printf(“enter a no ”);

scanf(“%d”,&n);

x=fact(n);

printf(“fact=%d”,x);

}

Explanation:-

fact(3);

{

return(3*fact(2));

fact(2){

return(2*fact(1));

}

fact(1);

{

return(1)

}

/*power program */

int power (int a,int b)

{

if (b= =1)

{

return(1);

}

else

{

return(a*power(a,(b-1)));

}

void main( )

{

int x,y,p;

printf(“enter two no”);

scanf(“%d%d”,&x,&y);

p=power(x, y);

printf(“%d”,p);

}

Note:-1.

Recursion may seem strong and complicated at the first stage. But it is often must way to code then algorithm and once with the recursion the easiest way doing so.

Pointer

pointer:-

pointer is variable that store address of another variable of the same data type by declaring a counter the name the name of the counter variable present by *(stric)

eg:-1

int *p,q;

p=&q;

printf(“%d”,p);

printf(%d”,&q);

printf(“%d”,*p);

eg:-2

main( )

{

int a=30,y=20;

int *p,*q;

q=&a;

p=&y;

printf(“%d%d”, *p,*q);

}

Find the Errors & output and also try to complete the program.

program:-eg:-3

int a=50;

int *p;

p=x;

printf(“%d”,p);

p++;

printf(%d”,p);

Array & pointer:-

Eg:-

int x[5]={1,2,3,4,5};

int*p;

p=x;

printf(%d”,*p);

p++;

printf(“%d”,*p);

Eg:-

int x[5]={1,2,3,4,5};

int *p;

int i;

p=&x[0];

p=x;

for(i=0;i<=4;i++)

{

printf(“%d”,(&p+i));

printf(“%d”,*(p+i));

}

Eg:-

int x[5]={3,5,9,8,12};

int *p, *q;

int i;

p=x;

q=&x[2];

q++;

p=q;

printf(“%d”,*p);

for(i=3;i>=0;i--)

{

printf(“%d”,i[x]);

}

Pointer and function:-

Eg:-

void abc(int*x)

{

printf(“%d”,*x);

void main( )

int a=50;

abc(*a);

}

Output:-

Eg:-

void abc(int*x)

{

*x=*x+10;

printf(“%d”,*x);

}

void main( )

{

int a=50;

abc(&a);

printf(“%d”,a);

}

Note:-

in pass by value if the formal parameter is change it will not effect the actual parameter but in case of pass by refrence if the formal parameter is change the actual parameter will also be change.

Note:-

As like we can pass the value of the array to a function we can pass the add of a variable as an argument to a function in the normal way.

Note:-

The process of calling a function using pointer to pass the add of variable is known as call by reference. The function which is called by change the value of the variable used

Array and pointer :-

Eg:-

char x[10]=”hello:”

p=x; or p=&x[0];

while (*p)

{

printf(“%c”,*p);

p++;

}

Eg:-

W A P lenth of string using pointer

main( )

{

charx[30],*p;

int n=0;

printf(“enter a string “);

gets(x);

p=x;

while(*p)

{

n++;

p++;

}

printf(“length=%d”,n);

}

Eg:-W A P compare two strings

main( )

{

char x[30],y[30];

printf(“enter the two string”);

gets(x);

p=x;

q=y;

while (*p)

{

if (*p!=*q)

{

printf(“string are not equal”);

break;

}

p++;

q++;

}

if (*p= = null)

{

printf(“string are equal”);

}

Pointer and structure :-

Eg:-

struct abc;

{

int x;

int y;

};

abc m={10,20};

abc *p;

p=&m;

printf(“%d%d”,p x, p y);

printf(“%d %d”,(*p).x, (*p).y );

Eg:-

main( )

{

struct date

{

int d, m, y;

};

date x[3]={{10, 9, 2006},{21, 11, 1988},{16, 5, 1988}};

date *p;

p=x;

int n;

for(n=1; n<=3; n++)

{

printf(“%d%d%d”, p d, p m, p y);

p++;

}

Eg :-

struct xyz

{

int a,b;

}

void modify(xyz *m)

{

m a+=5;

m a+=10;

}

xyz n={50, 60};

modify (&n);

printf (“%d%d%d”, n.a, n.b); }

The reason for using pointer are:-

1. First pointer provides the means by which function can modify calling argument.

2. pointer supports dynamic memory location.

3. pointer can improve the efficiency of certain routines.

4. * operator is also known as indirection operator

5. & operator is known as address of operator.

6. for printing address is an unsigned integer(%u)

note:-

& and * are known as unary operator.

Some rules for pointer :-

1. pointer declaration must have prefix to f*

2. while assigning variable to the pointer variable the address operator (&) must be used along with variable.

3. mix data type is not allowed.

Pointer arithmetic:-

As a pointer holds the memory add of a variable some airthmatic operations can be perform with pointersare:-

1. add

2. sub

3. increment ++

4. decrement –

eg :-

int value, *ptr;

value =120;

ptr=&value;

ptr++;

printf(“address =%u”,ptr);

note:-

(*ptr)++=++(*ptr)

Call by value:-

Whenever a portion of a program invokes a function with formal argument control will be transfer from the main( )to calling function and the value of actual argument is copied to the with in the function the actual value the calling portion of the program may be altered or changed when the control is transfer back from the function to the calling portion of the program .the actual value are not transferred back this type of passing formal argument to a function is technically known as call by value.

Call by reference:-

1. actual argument are copied on to the formal argument

2. it referred by the different variable names

3. the formal and actual argument referencing the some memory areas

Operators: An operator is a symbol that tells the computer to perform mathematical or logical manipulations. Operators are used in programs to manipulate data and variables. They usually form a part of the mathematical of logical expressions.

Operators can be classified into a number of categories. They include:

(1) Arithmetic operators.

(2) Relational operators.

(3) Logical operators.

(4) Assignment operators.

(5) Increment and decrement operators.

(6) Conditional operator.

(7) Bitwise operator.

(8) Special operators.

(1) Arithmetic operator : C provides all the basic arithmetic operators such as + , – , * , / , % .

OPERATORS MEANING

+ Addition or unary plus

– Subtraction or unary minus

* Multiplication

/ Division

% Modulo division

Example of arithmetic operators are a – b ,a + b ,a*b ,a / b ,a % b.

Here a and b are two variables and are known as operators.

Integer arithmetic ;- When both the operands in a single arithmetic expression such as a + b are integers. The expression is called an integer expression and the operand is called integer arithmetic.

Integer arithmetic always fields an integer value. Example , if a & b are integers , then for a = 14 & b = 4.

We have following results:

a + b = 18

a – b = 10

a * b = 56

a / b = 3 ( decimal part truncated )

a %b = 2 ( reminder of division )

(2) Real arithmetic : An arithmetic operation involving only real operands is called real arithmetic. A real operand may be assume values either in decimal or exponential notation.

Relational Operator

OPREATORS MEANING

< is less than

< = is less than equal to

> is greater than

> = is greater than equal to

= = is equal to

! = is not equal to

Logical operator : In addition to the relational operators ‘ C’ has following three logical operators.

&& meaning logical AND

| | meaning logical OR

! meaning logical NOT

The logical operator && and || are used when we want to test more than one condition and more decisions. An example is,

a > b && x = = 10

the logical expression is true only if a > 6 is true and x = = 10 is also true. If either ( or both ) of them are false ,the expression is false.

e.g. if x, y, & z are floats then we will have:

x = 6.0 / 7.0 = 0.857143

y = 1.0 / 3.0 = 0.33333

z = -2.0/3.0 = -0.666667

the operator % (modulo division ) can not be used with real operands.

(2) MIXED MODE ARITHMETIC : When one of the operand is real and other is integer , the expression is called a mixed mode arithmetic expression.

If either operand is of the real type then only the real operation is performed and the result is always a real number.

They 15 / 10.0 = 1.5

where as 15 / 10.0 = 1.0

(3) RELATIONAL OPERATOR : If we want to compare two quantities we use relational operator.

Example : we may compare the age of two persons , or the price of two items and so on these comparisons can be done with the help of relational operator.

Containing of relational operator is termed as a relation expression.

Example of relational operator is < , > , <= ,>= ,= = , !=

(4) Assignment operator: assignment operator are used to assign the result of an expression to a variable. We have seen the usual assignment operator ‘=’.

‘C’ has a set of ‘ shorthand’ assignment operators of the form.

v op = exp ;

where V is variable , exp is an expression and op is a known as the shorthand assignment operator.

SHORTHAND OPERATORS:

Statement with simple assignment operator	Statement with shorthand operator
a = a + 1	a + = 1
a = a – 1	a – = 1
a = a * ( n + 1)	a * = n + 1
a = a / ( n + 1)	a / = n + 1
a = a % b	a % = b

(5) INCREMENT AND DECREMENT OPERATOR:

‘C’ has two very useful operators not generally found in other language. These are the increment and decrement operator.

++ and – – The operator ++ adds 1 to the operand while – – substrates 1.

Types of increment and decrement operator :

(a) pre-increment ++m

(b) post- increment m++ (m+=1)

(d) post- decrement – – m

+ + m is equivalent to m = m+1

– – m is equivalent to m = m –1

We use increment and decrement statements in for and while loops.

(6) CONDITIONAL OPERATORS: A ternary operator pair ‘? : ‘ is available in C to construct conditional expressions of the form.

exp1 ? exp2 : exp3

where exp1 , exp2 and exp3 are expressions.

The operator ?: works as follows :-

If exp1 is true the answer will be exp2 else exp3

Example: a = 10;

b = 15;

x = ( a > b) ? a : b ;

printf”%d”,x);

if ( a>b)

x = a;

else x = b;

(7) SPECIAL OPERATOR :

‘C’ supports some special operator of interest such as comma operator, size of operator, pointer operator.

The comma operator :-

The comma operator can be used to link the related expressions together . For example , the statement

value = ( x = 10, y = 5 , x + y);

first assign the value 10 to x then assigns 5 to y and finally assigns 15 i.e., (10+5) to value.

NOTE : Please Ignore Human being typing mistakes

The size of operator:

The size of operator is a compile time operator and when used with an operand, it returns the numbers of bytes the operand occupies. The operand may be a variable , a constant or a data type qualifier.

Example ; m = size of (sum)

n = size of (long int.)

the size of operator is normally used to determine the length of arrays and structures when their sizes are not known to the programmer.

EXPRESSIONS

Algebraic expression	‘ C ’ expression
a * b – c (m + n) (x + y) ab/c 3x2 + 2x +1 x/y + c	a * b – c ( m + n ) * ( x + y) a * b/c 3xx + 2*x +1 x/y + c

EXPRESSION : There are two types of expressions .

(1) Arithmetic expression.

(2) Relational / Logical /Conditional expression.

An arithmetic expression is written numeric values an relational expression is either true or false. Arithmetic expressions uses arithmetic operators relational operators uses relational and logical operator.

Example of arithmetic expression :

a + b , a – b

a + ( a/b * d )

Example of relational expression :

a < b

a > b

( a || b) * ( a != b ) && ( c = = d)

!( a > b )

Note: There is almost no difference between relational expression and arithmetic expression both can be used in place of each other.

Zero –––– false

Non zero –––– true

If relational expression is true than returns numeric value 1 otherwise 0.

Example of logical operators:

AND –––––– &&

OR –––––– | |

NOT –––––– !

A	B	AB	A+B
0	0	0	0
0	1	0	1
1	0	0	1
1	1	1	1

(9) PRECEDENCE OPERATOR:

An arithmetic expression without parentheses will be evaluated from left to right using the rules of precedence of operators.

There are two distinct priority level of arithmetic operators.

High priority * , / , %

Low priority + , –

Firstly high priority operators are applied as they are encountered then low priority operators are applied.

Example : x = a- b/3 + c* 2-1

where a=9, b=12 ,and c=3

x = 9- 12/3 + 3*2-1

first pass step1 x = 9 – 4 + 3* 2 –1

step2 x = 9 – 4 + 6 –1

second pass step3 x = 5 + 6 –1

step4 x = 5 +5

step5 x = 1

Example. A && B , A || B , (!A) , (!A=B)

Hierarchy of operation:- (BODMOS)

Bracket, open, Divide, Multiply, Add, Subtraction.

Priority Operators

1^st * / %

2^nd + -

3^rd =

Example. 2*5 – 4/2 + 3*2

10 – 4/2 + 6

10 – 2 + 6

16 – 2

14 Ans.

Control structure :-

1. Decision control structure

2. loop control structure.

3. case control structure.

1. decision control structure:-

(a) if statement

(b) if – else statement

(a) Syntax of if statement:-

If (condition is true)

Execute this statement ;

Example. if (A = B)

{

Printf (“ marks are equal”);

}

If the condition is true than the statement is executed. If the condition is not true than the statement is not executed.

Multiple statement :-

if( condition )

{

Statement 1 ;

Statement 2 ;

}

(6) if – else condition

Example. Syntax.

if( condition )

{

Statement 1 ;

Statement 2 ;

}

else (condition )

{

Statement 3 ;

Statement 4 ;

}

Example. if ( A >= B )

{

printf(“ Drink tea “);

}

else

{

printf(“ Drink coffee ”);

}

Syntax:

if( condition )

{

if( condition )

{

Statement ;

}

else

{

Statement ;

}

Conditional operators : Ternary operators

Syntax: exp1? exp2 : exp3

if exp1 is true then the result will be exp2 else exp3. We can do similar with if-else statement.

Example.

int x, y;

scanf(“%d”,&x);

y=(x>5?3:4);

This statement will store 3 in y if x>5 otherwise it will store 4 in y.

Example.

char a;

int y;

printf(“Enter any character”);

scanf(“%c”, &a);

y=(a>65 && a<=90?1:0);

Note: It is not necessary that the conditional operator should be used only in arithmetic statements.

Modulus operator :-

c = a % b

a	b	C = a % b
10	2	0
11	2	1
11	7	4
13	7	6
24	8	0
7	21	7
132	10	2

Exercise: 153 % 10

7842 % 2

98 % 10

4 % 10

Else if ladder :-

Syntax: if(condition1)

Statement1;

else if (condition2)

Statement2;

else if (condition3)

Statement3;

else

default statement ;

Assignment operator :-

An assignment operator used to assign the value of any expression to a single variable.

Left value = Right value

It can be a single variable. A variable constant an expression

function call.

int x = 5; x = ( a++) + ( b–1) *c

int x = y; x = add( ) ;

Note :- The variables declared inside main function are called local automatic variable. The variables outside any function are called global variables. The local automatic variable are not initialized so these stores garbage or meaningless value till assign to some useful value , the global variables are automatically initialized by the system .

Global and Local Variable -:

Example.

#include < stdio.h >

int g ; // global variable

void main()

{

int a ; // local variable

printf(“ \n %d %d”,a ,g);

g + = a ;

printf(“ \n %d %d” ,a ,g);

}

NESTED IF STATEMENT

When a series of decisions are involved. We may have to use more than one if-else statement in nested form.

if( test condition-1 )

{

if( test ondition-2)

{ Statement 1;

}

else

{ Statement 2;

}

} else

{Statement 3;

}

If the condition-1 is false then the statement 3 is executed, otherwise it continues to perform the second test.

If the condition 2 is true statement 1 is executed otherwise statement 2 is executed. And then the control is transferred to the statement x.

The else – if ladder :

There is another way of putting if together when multipath decisions are involved. A multipath decision is a chain if in which the statement associated with each else is an if.

Syntax :

if( condition-1 )

statement-1;

else-if ( condition-2)

statement-2;

else-if ( condition-3)

statement-3;

else-if ( condition-n)

statement-n;

else

default-statement;

statement-x;

This construct is known as the else if ladder.

LOOPS

LOOPS: loops are use in programming for repeating a set of statement again and again till a logical condition is true. There are three types of loops:

(1) While loop

(2) For loop

(3) Do while loop

Important for loop :-

(1) initialization part

(2) condition

(3) update counter.

(1) for loop:

syntax: for(initialization ; condition ; updating)

example: for( i=0; i<5; i++ )

initialization condition increment

Note : when one or more statements are to be executed repeat loops are used.

· Looping is also called repetition or iteration.

· Looping can also be incremented with the help of go to statement but the go to statement is avoided in structure programming because it destroys the concept of “ locality of reference” . locality of references increase the efficiency of the memory axis.

· Example : for ( i =5; i>=0 ; i--)

i = 5 5 >= 0

i = 4 4 >= 0

i = 3 3 >= 0

i = 2 2 >= 0

i = 1 1 >= 0

i = 0 0 >= 0

Program:

# include < stdio.h >

# include < conio.h >

void main ()

{

int i;

for ( i = 0 ; i < = 5 ; i + +)

{

printf (“ \n %d ”,i);

}

getch( );

}

While loop :

void main ( )

{ int i;

i = 1;

while( i < = 10)

{

printf(“\n %d”, i);

printf(“Hello”);

i = i +1;

}

getch( );

}

Do-while loop:

void main ( )

{

int i ;

i = 1;

do {

printf(“ Hello ”);

printf(“ %d”,i);

i = i + 1;

}while ( i <= 10);

getch( ); }

Note: do-while loop is slightly differ from while loop and for loop. In this loop , the statements are printed and condition checking after them. And while has to be terminated at the last with semi colon. This loop is generally used in the menu design.

Error in loops: The errors in loops are caused due to incorrect condition. Error may be three types:

(1) infinite looping

(2) for breaking a infinite loop we use “ Ctrl + break ” .

(3) Syntax error.

Nested for loop : loop with in loop is called nested loop. First loop is outer loop and second loop is inside loop.

Outer loop

Syntax: for( condition )

{ inner loop

for ( condition )

{

Statement;

}

Program:

# include < stdio.h >

# include < conio.h >

void main ( )

{

int x, y;

for ( x = 1 ; x < = 5 ; x + +)

{

for ( y = 1 ; y < = x ; y + +)

{

printf(“ Hello”);

}

printf(“\n”);

}

getch( );

}

Switch statement :

We have seen that when one of the many alternatives is to be selected , we can use an if statement to control the selection. However the complexity of a such a program increases when the number of alternative increases. The program becomes difficult to read and follow. To overcome this difficulty, ‘C’ has a built in multiway decision statement knows as switch.

The switch statement tests the value of a given variable or expression against a list of case.

Syntax:

Switch ( expression)

{

case value – 1:

block 1

break;

case value – 2:

block 2

break;

……….………

……………….

default:

default block

break;

}

Loop with break : -

(1) while ( )

{ ______________

______________

if (condition )

break ;

______________

}

(2) for ( )

{ ______________

______________

if ( error )

break;

______________

}

(3) while ( )

{ ______________

if (error )

goto stop ;

______________

if ( condition )

goto abc ;

______________

abc:

______________

stop:

}

Example: Menu:

1. Add.

2. Sub.

3. Div.

4. Mul.

Choose any one option.

Example program:

# include < stdio.h >

# include < conio.h >

void main ( )

{

int i = 2;

switch (i)

{

case 1: printf(“ My case one”);

break ;

case 2: printf(“ My case two”);

break ;

default: printf(“ I am in default”);

break ;

}

Example 2:

void main ( )

{

int i ;

printf(“ Enter any number for choice.”);

scanf(“ %d”, &i);

switch( i )

{

case 1: printf(“\n Cold drink”);

break;

case 2: printf(“\n Coffee”);

break;

default: printf(“\n Not available”);

break;

}

getch();

}

Note: We can also use character type option.

e.g., char ch;

switch (ch )

{ case ‘ A’ : Do this;

break;

}

break statement : we use break state in two cases.

(1) Switch case.

(2) Looping.

When the keyword break is use it controls the loop.

Example. void main ( )

{

int i = 1,j = 1;

while (i++ < = 200)

{

if ( j = = 150 )

break ;

else

printf( “ %d %d \n”, i, j) ;

}

Example :

void main( )

{

int i = 1;

while ( i <= 200)

{

if( i == 100)

break ;

else

printf(“ %d”,i);

i ++;

}

getch();

}

THE CONTINUE STATEMENT :

This statement is used in looping an switch statement when condition is true than loop start again.

Example : int value , i ;

i = 0;

while (i<=10)

{

printf(“ Enter a number :”);

scanf(“ %d” ,&value);

if(value <= 0)

{

printf(“ zero or negative value found ”);

continue ;

}

i ++;

}

go-to statement : go-to statement is use for line changing. It is not useful for a good programming skill. There are some limits in go-to statement. Firstly check the condition if condition is true then control transfer to the particular line or label. It is time consuming process. It is difficult to de-bug a program.

The big problem with go-to is that when we use them we can never be sure how we got a certain point in our code. That means flow of control is not clear so we neglect the go-to statement.

Example:

main( )

{

int goals;

printf(“ Enter numbers:”);

scanf(“ %d”, &goals);

if( goals<=5)

goto score;

else

{

printf(“Good Score”);

exit();

}

score:

printf(“To error is by human”);

}

Note: In this program we have to use #include <process.h> because the function exit() belongs inside that header file.

CHARACTER

The character that can be used to form words, numbers and expressions depend upon the computer on which the problem is run.

The char. In ‘C’ are grouped into the following categories :

(1) Letters.

(2) Digits.

(3) Special char.

(4) White spaces.

CHARACTER SET

Letters Digits

Uppercase A……Z All decimal digits 0…9

Lowercase a…….z

SPECIAL CHARACTERS

,	Comma
.	Period
;	Semicolon
:	Colon
?	Question mark
“	Quotation mark
/	Slash
\	Backslash
_	Underscore
%	Percentage
\|	Vertical bar
#	Number sign
$	Dollar sign
&	Ampersand sign
-	Minus sign
<	Less than
>	Greater than
+	Plus sign
[	Left bracket
]	Right bracket
{	Left brace
}	Right brace
(	Open bracket
)	Close bracket
!
	White spaces
	Blank spaces
	Horizontal tab
	New line
	Form feed

Print format codes:-

% i -- Signed decimal number

% u -- Unsigned decimal number

% x -- Hex decimal number

Reading a character :

By using getchar( ) function we can take value from keyboard one by one character. It is similar to scanf( ) function. But difference is that reading a single character only.

Example: (1) char ch;

ch = getchar( );

(2) char ch ;

ch = ‘ ‘ ;

while ( ch != ‘\n’)

{

ch = getchar( );

}

Character test function:

(1) isalpha( )

(2) isdigit( )

(3) islower( )

(4) isupper( )

(5) isspace( )

all of above are belong into the ctype.h header file.

Example:

#include < stdio.h >

#include < conio.h >

void main( )

{

int i, j;

clrscr( );

for ( i = 1; i <= 5 ; i++ )

{

for ( j = 1; j <= i ; j++)

{

printf( “ %d ”, i );

}

printf( “ \n ” );

}

getch( );

}

Writing a character :

By putchar( ) function we can put the value on screen.

putchar ( variable name) ;

it is similar to printf ( ) function , but we never use formatting like %d , %f ,and we can not print multiple value . no commands are allow.

Example: char ch;

ch = getchar ( );

putchar( ch );

Formatted input :

By using scanf( ) function we take the value from keyboard.

Syntax : scanf( “control string”, &arg1, &arg2 ,&arg3….);

Blank, tabs, \n ( new line ) are ignore. For reading a integer number is

%wd.

where , w = width

The % sign indicates that a conversion specification follows :

w = “ is an integer number. “

Example : Scanf(“ %d %d %d”, &a ,&b, &c);

Formatted output: By printf( ) function, we can printf( ) the value or message on the screen.

Syntax : printf( “control string ”, arg1 ,arg2…);

Three types of items control string contains :

(1) Print character or value.

(2) Output format.

(3) Escape sequence character such as \n ,\t,..

Example:

printf(“ a =%f \n b = %f” ,a ,b);

printf(“ sum =%d “ , 1234);

printf(“ \n \n ”);

Example:

printf(“ %6d” ,9876);

printf(“ %2d “ , 9876);

Example:

printf(“ %7.2f ”, number);

Type casting :- or cast operator :

The general format of cast type expression:

Example:

float a ;

int x = 6 , y = 4;

a = float (x/y);

printf(“ %f”, a);

The cast operator is technique to force fully convert one data type to the other this process is known as type casting.

Example: float a =1.23;

printf(“ Value of an type casting = %d” int(a));

printf(“ value of a = %f” , a) ;

Result : 1^st :- 1

2^nd :- 1.230000

C Language Summary

Table of Contents

Arrays

An array is defined by writing the data type followed by the name followed by the size in brackets; for example,

int x[20];

double car[ROWS][COLS];

In the first case, the variables x[0], x[1], ... ,x[19] are created. In the second case, a 2-D array (matrix) is created. In C, array names without the brackets are pointers.

Return to Table of Contents

Break

When the statement

break;

is encountered, the innermost while, do while, for, or switch construct is terminated.

Return to Table of Contents

Cast

The cast operator is written as

(type)

where type is a data type. When the cast operator is executed, the operand is converted to type. As examples, if we write:

int i = 2;

float x;

x = (float) i;

the value of i is converted to float and copied into x. If we write:

struct node {

char* data;

struct node* link;

};

struct node* ptr;

ptr = malloc(sizeof (struct node));

storage for one structure whose members are data and link is allocated by the library function malloc. The address of this storage is assigned to ptr.

Return to Table of Contents

Comments

A C comment is delimited by /* and */.

Return to Table of Contents

Constants

Integer constants may be written in decimal:

130 45 88203

An integer constant that begins with 0 (zero) is an octal number:

0130 045

A sequence of digits preceded by 0X or 0x is a hexadecimal number:

0x90A 0Xf2

Either lowercase a through f or uppercase A through F is acceptable.

An integer constant may be terminated by u or U, to indicate that it is unsigned, or by l or L to indicate that it is long. If a decimal constant is not terminated with either u, U, l, or L, it is the first of the types int, long, or unsigned long in which its value can be represented. If an octal or hexadecimal constant is not terminated with either u, U, l, or L, it is the first of the types int, unsigned int, long, or unsigned long in which its value can be represented. If a decimal, octal, or hexadecimal constant is terminated with either u or U, it is the first of the types unsigned int or unsigned long in which its value can be represented. If a decimal, octal, or hexadecimal constant is terminated with either l or L, it is the first of the types long or unsigned long in which its value can be represented. If a decimal, octal, or hexadecimal constant is terminated with either l or L and u or U, it is of type unsigned long.

A floating-point constant consists of a string of digits (integral part) followed by a decimal point followed by a string of digits (fractional part) followed by an integer exponent. The integer exponent is e or E optionally followed by + or followed by a string of digits. Either the integral part or the fractional part, but not both, may be omitted. Either the decimal point or the integer exponent, but not both, may be omitted. Examples of floating-point constants are:

2.0 4.3e4 9.21E9 13.E+4 4e3 .390

A floating-point constant may be terminated by f or F to indicate that it is a float or by l or L to indicate that it is a long double. If a floating-point constant is not terminated with either f, F, l, or L, it is of type double.

A char constant is delimited by single quotation marks, for example, 'Y'.

A string constant is delimited by double quotation marks, for example,

"This is a string constant."

C recognizes the following escape sequences in character and string constants:

Constant	Meaning
\a	Ring bell (alert)
\b	Backspace
\f	Formfeed
\n	Newline
\r	Carriage return
\t	Horizontal tab
\v	Vertical tab
\\	Backslash
\'	Single quote
\"	Double quote
\?	Question mark
\ddd	Octal constant
\xhh	Hexadecimal constant

Return to Table of Contents

Continue

When the statement

continue;

is encountered in a while or do while loop, control passes to the condition that determines whether to execute the body of the loop again. When the statement

continue;

is encountered in a for loop, control passes to the update statement, expr3, in

for (expr1; expr2; expr3) body

Then expr2 is evaluated to determine whether to execute body again.

Return to Table of Contents

Data Types

The integer data types are char, short int (which may be abbreviated short), int, and long int (which may be abbreviated long). The sizes of these data types satisfy

sizeof(char) <= sizeof(short) <= sizeof(int) <= sizeof(long)

The signed integer types are signed char, signed short int, signed int, and signed long int. In addition, the unsigned integer types unsigned char, unsigned short int, unsigned int (which may be abbreviated unsigned), and unsigned long int are available.

The floating-point data types are float, double, and long double. The sizes of these data types satisfy

sizeof(float) <= sizeof(double) <= sizeof(long double)

Some other types, defined in standard headers, are given in the following table:

Type	Defined in	Represents
ptrdiff_t	stddef.h	The difference of two pointers
size_t	stddef.h stdio.h stdlib.h string.h time.h	The value of sizeof
va_list	stdarg.h	Information needed by macros in stdarg.h
FILE	stdio.h	Information needed to manipulate files
fpos_t	stdio.h	A position within a file
clock_t	time.h	Time
time_t	time.h	Time

Arrays	Break	Case (see Switch)
Cast	Comments	Constants
Continue	Data Types	#Define
Do While	Enum	For
Functions	If	Initializing in Definitions
Keywords	Pointers	Operators and Precedence
Return	Sizeof	Standard Headers
Storage Classes	Structures	Switch
Typedef	Type Qualifiers	Union
Void	While	Bibliographic References

Header File	Purpose
assert.h	Putting diagnostics into programs
ctype.h	Testing and modifying characters
errno.h	Reporting error conditions
float.h	Describing floating-point types
limits.h	Describing integer types
locale.h	Formatting numeric values
math.h	Mathematical functions
setjmp.h	Bypassing default function call and return conventions
signal.h	Handling signals
stdarg.h	Writing functions with an arbitrary number of arguments
stddef.h	Common definitions
stdio.h	Handling input and output
stdlib.h	General utilities
string.h	Handling arrays of characters
time.h	Handling time

ITM UNIVERSITY, CSE, SECTION B

Saturday, 22 December 2012

C ASSIGNMENT & PROGRAM LIST

ESSENTIAL OF IT (C LANGUAGE) [1st year]

Multi dimensional array:-

Find out the maximum & smallest number with the help of array

Program

Test this program using different type of string

Program-:

Output:-

Program

Program

There are three types of sorting:-

Selection Sort:-

Output:-

Bubble Sort:-

Insertion sort:-

Declaring and initializing string variable:-

Output:- 10

Output :-

Output:-

Advance feature of functions:-

Output :-

Output:-

Output::-

Recursion:-

Explanation:-

Note:-

Pointer arithmetic:-

Call by reference:-

Ajay Pachauri

Description	Operator(s)	Associates from the
Function expression Array expression Struct indirection Struct member	( ) [ ] -> .	left
Increment/decrement One's complement Negation Address of Dereference Type cast Unary minus Unary plus Size in bytes	++ -- ~ ! & * (type) - + sizeof	right
Multiplication Division Remainder	* / %	left
Addition Subtraction	+ -	left
Shift left Shift right	<< >>	left
Less than Less than or equal Greater than Greater than or equal	< <= > >=	left
Equal Not equal	== !=	left
Bitwise and	&	left
Bitwise exclusive or	^	left
Bitwise inclusive or	\|	left
Logical and	&&	left
Logical or	\|\|	left
Conditional	? :	right
Assignment	= %= += -= *= /= >>= <<= &= ^= \|=	right
Comma	,	left