func_code_string: #include <bits/stdc++.h>   using namespace std;   const int INF = (int)1e9;   const int EPS = 1e-6;   const int mod = 1000000007;   const long double PI = 3.14159265359;   const int dx4[4] = {0, 1, 0, -1};   const int dy4[4] = {-1, 0, 1, 0};   const int dx8[8] = {-1, -1, -1, 0, 1, 1, 1, 0};   const int dy8[8] = {-1, 0, 1, 1, 1, 0, -1, -1};   inline bool grid_inside(int x, int y, int n, int m) {     return x >= 1 && x <= n && y >= 1 && y <= m;   }   template <typename T>   T lcm(T a, T b) {     return (a * b) / __gcd(a, b);   }   template <typename T>   T Dis(T x1, T y1, T x2, T y2) {     return sqrt(((x1 - x2) * (x1 - x2)) + ((y1 - y2) * (y1 - y2)));   }   template <typename T>   T Angle(T x1, T y1, T x2, T y2) {     return atan((double)(y1 - y2) / (double)(x1 - x2));   }   inline int Set(int N, int pos) { return N = N | (1 << pos); }   inline int Reset(int N, int pos) { return N = N & ~(1 << pos); }   inline bool Check(int N, int pos) { return (bool)(N & (1 << pos)); }   template <class T, class X>   inline T togglebit(T a, X i) {     T t = 1;     return (a ^ (t << i));   }   bool compare(const pair<int, int>& i, const pair<int, int>& j) {     return i.first < j.first;   }   int LSOne(long long int n) { return log2(n & -n) + 1; }   int rangeClear(int n, int i, int j) {     int ones = ~0;     int a = ones << (j + 1);     int b = (i << 2) - 1;     int mask = a | b;     int ans = n & mask;     return ans;   }   long long int mul_mod(long long int x, long long int y, long long int mod) {     long long int i = 0, j = x;     while (y > 0) {       if (y & 1) {         i = (i + j) % mod;       }       j = (j + j) % mod;       y >>= 1;     }     return i;   }   long long int fast_power(int a, int x) {     if (x == 0)       return 1;     else if (x == 1)       return a;     else {       long long int R = fast_power(a, x >> 1);       if (!(x & 1))         return R * R;       else         return R * a * R;     }   }   long long int fast_power_unlocked(long long int a, long long int n,                                     long long int mod) {     long long int res = 1;     while (n > 0) {       if (n & 1) {         res = mul_mod(res, a, mod);       }       a = mul_mod(a, a, mod);       n = n >> 1;     }     return res;   }   long long int modInverse(long long int A, long long int M) {     return fast_power_unlocked(A, M - 2, M);   }   const int maxn = 1e5 + 5;   vector<int> g[maxn];   bool ok;   int p[maxn], h[maxn], hp[maxn], vis_cnt[maxn];   void dfs(int src, int par) {     vis_cnt[src] = p[src];     int thp = 0;     for (auto x : g[src]) {       if (x == par) continue;       dfs(x, src);       thp += hp[x];       vis_cnt[src] += vis_cnt[x];     }     if ((vis_cnt[src] + h[src]) % 2 == 1) ok = false;     hp[src] = (vis_cnt[src] + h[src]) / 2;     if (vis_cnt[src] + h[src] < 0) ok = false;     if (hp[src] >= 0 && (vis_cnt[src] >= hp[src])) {     } else       ok = false;     if (thp > hp[src]) ok = false;   }   void solve() {     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 x, y;       cin >> x >> y;       --x;       --y;       g[x].emplace_back(y);       g[y].emplace_back(x);     }     ok = true;     dfs(0, -1);     if (ok)       cout <<  YES ;     else       cout <<  NO ;     for (int i = 0; i < n; i++) g[i].clear();   }   int main() {     ios::sync_with_stdio(false);     cin.tie(nullptr);     ;     for (auto blockTime = make_pair(chrono::high_resolution_clock::now(), true);          blockTime.second;          fprintf(stderr,  %s: %ld ms n ,  Time Taken ,                  chrono::duration_cast<chrono::milliseconds>(                      chrono::high_resolution_clock::now() - blockTime.first)                      .count()),               fflush(stderr), blockTime.second = false) {       int t;       cin >> t;       for (int i = 0; i < t; ++i) {         solve();         cout <<   n ;       }     }   }   