func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 2e5 + 5;   const long long inf = 1e12;   int n, h[N], w[N], u, v;   long long ans, f[N][2];   vector<int> g[N];   void dfs(int u, int fa) {     vector<long long> vec;     long long sum = 0;     for (auto v : g[u]) {       if (v ^ fa) {         dfs(v, u);         sum += f[v][0];         vec.push_back(f[v][1] - f[v][0]);       }     }     sort(vec.begin(), vec.end());     for (int t = 0; t < 2; ++t) {       f[u][t] = inf;       if (u > 1 && ((!t && h[fa] > h[u]) || (t && h[fa] < h[u]))) {         continue;       }       int out = vec.size() + t;       long long cur = sum;       for (int i = 0; ~out; ++i, --out) {         if (i && i <= vec.size()) {           cur += vec[i - 1];         }         f[u][t] =             min(f[u][t], cur + 1ll * w[u] * max(out, (int)g[u].size() - out));       }     }   }   int main() {     scanf( %d , &n);     for (int i = 1; i <= n; ++i) {       scanf( %d , &w[i]);     }     for (int i = 1; i <= n; ++i) {       scanf( %d , &h[i]);     }     for (int i = 1, u, v; i < n; ++i) {       scanf( %d%d , &u, &v);       g[u].push_back(v);       g[v].push_back(u);     }     dfs(1, 0);     printf( %lld n , f[1][0]);     return 0;   }   