Determine whether it is a prime number

#include<stdio.h>

bool IsPrime(int val) //this is a function that restricts the following main part and then returns in
{
int i;
for (i = 2; i < val; ++i)
{
if (val%i ==0)
break;
}

if (i ==val)
return true;

else
return false;
}

int main(void)
{
int m;

scanf("%d",&m);

if (IsPrime(m))
printf("yes!\n",m);

else
printf("no!n",m);

return 0;

}

// Prime numbers cannot be negative February 3, 2018 23:01:33