Codeforce - T-Primes

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define fastread()(ios_base::sync_with_stdio(false),cin.tie(NULL));

#define SZ  100000004
bool prime[SZ];
void primeset()
{
    ll i,j;
    prime[0] = prime[1] = true;

    for (i=4; i<SZ; i+=2)
        prime[i] = true;

    for (i=3; i*i<=SZ; i+=2)
        if (!prime[i])
            for (j=i*i; j<SZ; j+=2*i)
                prime[j] = true;
}
int main()
{
    fastread();
    primeset();
    ll t;
    scanf("%I64d",&t);
    while(t--)
    {
        ll n;
        scanf("%I64d",&n);
        ll r=sqrt(n);
        if(!prime[r] && r*r==n)
            printf("YES\n");
        else
            printf("NO\n");
    }
    return 0;
}