9) Write a program to check whether the given number is a prime number or not.(use of While loop)

 source file name: primeno.C

void main()

{

int n,m=0;

int d,op=0;

clrscr();

printf("\n enter any no:");

scanf("%d",&n);

m=n/2;

d=2;

while(d<=m)

{

if(n%d==0)

{

printf("\n given no is not Prime no");

op=1;

break;

}

else

d++;

}

if(op==0)

printf("\n given no is Prime no ");

getch();

}

output:

1. enter any no: 11

given no is Prime no 

2. enter any no: 20

given no is not  Prime no