func_code_string: #include <bits/stdc++.h>   using namespace std;   int light[3000];   int agr[3000];   int main() {     int n;     scanf( %d , &n);     int m = pow(2, n + 1) - 1;     for (int i = 2; i <= m; i++) {       scanf( %d , &light[i]);     }     int ans = 0;     for (int i = m; i >= 3; i--) {       if (i % 2 == 0) continue;       int a = light[i] + agr[i];       int b = light[i - 1] + agr[i - 1];       int c = a;       if (a != b) {         c = max(a, b);         ans += abs(b - a);       }       agr[i / 2] = c;       agr[(i - 1) / 2] = c;     }     printf( %d n , ans);     return 0;   }   