func_code_string: #include <bits/stdc++.h>   const int maxn = 105;   int a[maxn];   inline int max(int a, int b) { return a > b ? a : b; }   int main() {     int n, ans = 0, temp;     scanf( %d , &n);     for (int i = 1; i <= n; i++) scanf( %d , &a[i]);     if (n < 3 || n % 2 == 0)       puts( -1 );     else {       for (int i = (n - 1); i >= 1; i -= 2) {         temp = max(a[i], a[i + 1]);         ans += temp;         a[i / 2] -= temp;         if (a[i / 2] < 0) a[i / 2] = 0;       }       ans += a[1];       printf( %d n , ans);     }     return 0;   }   