This program is for finding that number is prime or not. Prime no. are those numbers which ,divide by 1 and itself only. For example

*7,13, etc.*

**C program to check number is prime or not**

#include<stdio.h>

void main()

{

int no,i,flag=0;

clrscr();

printf("Enter a no::");

scanf("%d",&no);

for(i=2;i<no;i++)

{

if(no%i==0)

{

flag=1;

}

}

if(flag==1)

{

printf("Number is not prime no.");

}

else

{

printf("Number is a prime no.");

}

getch();

}

it should be for(I=1) not for(I=2).......

ReplyDeleteno friend its i=2 because prime number is divisible by itself. If we set i=1 than all number%i is true(11%1==0) and flag will be 1 so it shows that 11 is not prime thats why we need to start loop from 2 instead of 1.

Delete