# What is wrong with my code for the problem PRB01(beginner)?

#include <stdio.h>

int main(void) {
int n;
scanf("%d\n",&n);
while(n–)
{
int num,c=0;
scanf("%d\n",&num);
for(int j=1;j<=num;j++)
{
if(num%j==0)
c++;
}
if (c==2)
printf(“Yes\n”);
else
printf(“no\n”);
}
return 0;
}

1 Like

There are many mistakes in your code.

1. `for(int j=1;j<=num;j++)`- for checking if a number is prime or not using bruteforce we divide the number by 2…n-1, so correct syntax would be `for(int j = 2;j<=num-1;j++)`
2. if c>0 which means the number is not prime
3. if c == 0 then you’re suppose to print ‘yes’ else ‘no’ (needs to be in lowercase)

Few corrections in your code: https://www.codechef.com/viewsolution/23411470

I agree with your logic sir, but I have checked the number of factors for a number and if they are two, then it will be prime and if not, it won’t be a prime number. Is my logic wrong?

Hi @mampy_21
Here I have fixed your code.
Your logic is correct. The only mistake you had was that you printed Yes instead of yes. The tester is case sensitive and thus it gave you WA.