Prime or not error can just tell what mistake I have made in my code and I need to y flag is used for

Question

#include <stdio.h>
int main()
{
int num,i, flag=0;
printf ("enter a number");
scanf("%d",&num);
for(i=2;i<num/2;i++)
{
if(i%num==0){
flag=1;
printf("not a prime number",num);
break;
}
if(flag == 0)
{       printf ("%d is a prime number",num);    
}
}
return 0;
}

// CAN U CHECK THIS PROGRAM//
IT DISPLAYS ALL AS PRIME NUMBER \\ AND NEED EXPLAIN ION Y FLAG IS USED

Answer 1

Dilip Hamilton

Problem is in your print statement.

flag is used to set value if condition is satisfied. It's a kind of decesion making to check whether number is prime or not. If number is not prime then we set flag 1. Now we can check later if flag is 0 then number is prime otherwise not. You can make flag boolean also.

Answer 2

Can u tell what's the error here AJ Anant - C#/Java Challenger