C language to distinguish prime numbers

What is a prime number: A positive integer, if there are only 1 and its own two factors, it is called a prime number, also known as a prime number.

Used: bool flag = 1; break;

Code section

int i,n,j;

bool flag = 1;

scanf("%d",&n);

for(i=2;i<=n/2;i++)

{

     if(n%i == 0)

     flag=0;

     break;
}

if(flag) 

{

     printf ("% n is a prime number", n);

}else{

      printf ("% n is not a prime number", n);

}