func_code_string: #include <bits/stdc++.h>   using namespace std;   const int N = 1e5 + 6;   bool flag = true;   vector<int> v[N];   int a[N], p[N], h[N], g[N];   void dfs(int u, int temp = -1) {     a[u] = p[u];     int sum = 0;     for (auto x : v[u]) {       if (x == temp) continue;       dfs(x, u);       sum += g[x];       a[u] += a[x];     }     if ((a[u] + h[u]) % 2 != 0) flag = false;     g[u] = (a[u] + h[u]) / 2;     if (g[u] >= 0 and g[u] <= a[u]) {     } else       flag = false;     if (sum > g[u]) flag = false;   }   int main() {     long long int t;     cin >> t;     while (t--) {       int n, m;       cin >> n >> m;       for (int i = 0; i < n; i++) cin >> p[i];       ;       for (int i = 0; i < n; i++) cin >> h[i];       ;       for (int i = 0; i < n - 1; i++) {         int a, b;         cin >> a >> b;         a--;         b--;         v[a].push_back(b);         v[b].push_back(a);       }       dfs(0);       cout << (flag ?  YES  :  NO ) << endl;       flag = true;       for (int i = 0; i < n; i++) v[i].clear();     }   }   