func_code_string: #include <bits/stdc++.h>   using namespace std;   int n;   int main() {     scanf( %d , &n);     long long ans = 0;     int cur = 0;     for (int i = 0; i < n; ++i) {       int a;       scanf( %d , &a);       int p = min(cur, a / 2);       a -= p * 2, cur -= p, ans += p;       ans += a / 3, a %= 3;       cur += a;     }     printf( %lld n , ans);     return 0;   }   