#include <bits/stdc++.h>   using namespace std;   const int N = 5e5 + 7;   int a[N], h[N], f[N << 2], lazy[N << 2];   vector<int> p[N], g[N];   struct node {     int fi, id, se;   } b[N];   void dfs(int x, int fa) {     b[x] = b[fa];     if (h[x] <= b[x].fi) {       b[x].se = b[x].fi;       b[x].fi = h[x];       b[x].id = x;     } else {       if (h[x] < b[x].se) b[x].se = h[x];     }     for (int v : p[x])       if (v != fa) {         dfs(v, x);       }   }   void built(int x, int l, int r, int n) {     if (l == r) {       f[x] = -(n - l + 1);       return;     }     int mid = (l + r) / 2;     built(x << 1, l, mid, n);     built(x << 1 | 1, mid + 1, r, n);     f[x] = min(f[x << 1], f[x << 1 | 1]);   }   void push_down(int x) {     f[x << 1] += lazy[x];     lazy[x << 1] += lazy[x];     f[x << 1 | 1] += lazy[x];     lazy[x << 1 | 1] += lazy[x];     lazy[x] = 0;   }   void update(int x, int l, int r, int left, int right, int y) {     if (left > r || right < l) return;     if (left <= l && right >= r) {       f[x] += y;       lazy[x] += y;       return;     }     push_down(x);     int mid = (l + r) / 2;     update(x << 1, l, mid, left, right, y);     update(x << 1 | 1, mid + 1, r, left, right, y);     f[x] = min(f[x << 1], f[x << 1 | 1]);   }   int R;   void query(int x, int l, int r) {     if (f[x] >= 0) return;     if (l == r) {       R = l;       return;     }     push_down(x);     int mid = (l + r) / 2;     if (f[x << 1 | 1] < 0)       query(x << 1 | 1, mid + 1, r);     else       query(x << 1, l, mid);   }   bool cmp(int x, int y) { return b[x].se < b[y].se; }   int main() {     int n;     scanf( %d , &n);     for (int i = 1; i <= n; i++) scanf( %d , &h[i]);     for (int i = 1; i < n; i++) {       int u, v;       scanf( %d%d , &u, &v);       p[u].push_back(v);       p[v].push_back(u);     }     int k;     scanf( %d , &k);     for (int i = 1; i <= k; i++) scanf( %d , &a[i]);     sort(a + 1, a + k + 1);     b[0] = {(int)2e9, 0, (int)2e9};     dfs(1, 0);     built(1, 1, k, k);     for (int i = 1; i <= n; i++) {       g[b[i].id].push_back(i);       int t = upper_bound(a + 1, a + k + 1, b[i].fi) - a - 1;       update(1, 1, k, 1, t, 1);     }     if (f[1] >= 0) {       printf( 0 );       return 0;     }     int ans = 2e9;     for (int i = 1; i <= n; i++)       if (g[i].size()) {         sort(g[i].begin(), g[i].end(), cmp);         int len = g[i].size(), tmp = -1;         for (int j = 0; j < len; j++) {           int t = upper_bound(a + 1, a + k + 1, b[g[i][j]].fi) - a - 1;           update(1, 1, k, 1, t, -1);         }         for (int j = 0; j < len; j++) {           int t = upper_bound(a + 1, a + k + 1, b[g[i][j]].se) - a - 1;           R = 0;           query(1, 1, k);           if (tmp == -1 && f[1] + len - j >= 0 && R <= t) {             tmp = a[R];           }           update(1, 1, k, 1, t, 1);         }         for (int j = 0; j < len; j++) {           int t = upper_bound(a + 1, a + k + 1, b[g[i][j]].se) - a - 1;           update(1, 1, k, 1, t, -1);         }         for (int j = 0; j < len; j++) {           int t = upper_bound(a + 1, a + k + 1, b[g[i][j]].fi) - a - 1;           update(1, 1, k, 1, t, 1);         }         if (tmp != -1) {           ans = min(ans, tmp - h[i]);         }       }     if (ans == 2e9)       printf( -1 );     else       printf( %d , ans);     return 0;   }