func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int ent;     long long int a, b;     cin >> ent;     while (ent--) {       int div = 0, pls = 0;       cin >> a >> b;       if (a % b == 0) {         cout << 0 << endl;         continue;       }       div = a / b;       pls = (div + 1) * b;       cout << pls - a << endl;     }   }   