func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long int t;     cin >> t;     while (t--) {       long long int n, m, sum = 0;       cin >> n >> m;       long long int a[5] = {0};       if (n == 1)         cout <<  0  << endl;       else if (n == 2)         cout << m << endl;       else         cout << (2 * m) << endl;     }   }   