func_code_string: #include <bits/stdc++.h>   using namespace std;   bool prime(long long x) {     if (x == 2) return 1;     if (x % 2 == 0) return 0;     for (long long j = 3; j * j <= x; j += 2) {       if (x % j == 0) return 0;     }     return 1;   }   int main() {     long long t;     cin >> t;     while (t--) {       long long n, m;       cin >> n >> m;       if (n - m > 1) {         cout <<  NO  << endl;       } else {         if (prime(n + m)) {           cout <<  YES  << endl;         } else {           cout <<  NO  << endl;         }       }     }   }   