func_code_string: #include <bits/stdc++.h>   using namespace std;   const int n = 10000000;   bitset<n> b;   vector<int> v;   void sieve() {     b.set();     b[0] = 0;     b[1] = 0;     for (long long i = 2; i <= n; i++) {       if (b[i]) {         v.push_back(i);         for (long long j = i * i; j <= n; j = j + i) {           b[j] = 0;         }       }     }   }   bool large_prime(long long no) {     if (no <= n) {       if (b[no]) {         return true;       } else {         return false;       }     }     for (long long i = 0; v[i] * (long long)v[i] <= no; i++) {       if (no % v[i] == 0) {         return false;       }     }     return true;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     int t;     cin >> t;     sieve();     long long a, b;     while (t--) {       cin >> a >> b;       if (a - b == 1) {         long long ans = (a - b) * (a + b);         if (large_prime(ans)) {           cout <<  YES                 <<   n ;         } else {           cout <<  NO                 <<   n ;         }       } else {         cout <<  NO               <<   n ;       }     }   }   