Count Primes

class Solution {
public:
int countPrimes(int n) {

if(n <= 2) return 0;

int res = 1;
for(int i = 3;i < n; i+=2){
int bound = sqrt(i),j;
for(j = 3; j <= bound; j+=2)
{
if(i%j == 0) break;
}
if(j > bound) ++res;
}

return res;
}
};