func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false), cin.tie(0);     int opx, t, c;     cin >> t >> c;     int dfx = 1;     long long lorenzo = 0;     while (c--) {       cin >> opx;       if (dfx != 1) lorenzo += t - dfx + 1;       dfx = opx + 1;     }     cout << lorenzo;   }   