func_code_string: #include <bits/stdc++.h>   using namespace std;   int arr[200000 + 10];   int arr2[200000 + 10];   int main() {     int n, num1 = 0, num2 = 0, tem1, l1 = 0, l2 = 0, num = 0;     long long ans = 0;     cin >> n;     for (int i = 0; i < n; i++) {       cin >> tem1;       if (tem1 == 0) {         ans += num;       } else         num++;     }     cout << ans;     return 0;   }   