func_code_string: #include <bits/stdc++.h>   using namespace std;   void solve() {     long long int n, m;     cin >> n >> m;     if (n == 1) {       cout <<  0  << endl;       return;     }     if (n == 2) {       cout << m << endl;       return;     }     if (n > 2) {       cout << 2 * m << endl;       return;     }   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long int t;     cin >> t;     while (t--) {       solve();     }     return 0;   }   