func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int a[6];     for (int i = 0; i < 6; i++) {       cin >> a[i];     }     int ans = (a[0] + a[1] + a[2]) * (a[0] + a[1] + a[2]) - a[0] * a[0] -               a[2] * a[2] - a[4] * a[4];     cout << ans << endl;     return 0;   }   