#include <bits/stdc++.h>   using namespace std;   const int N = 6010;   vector<int> a[N];   int L[N], cnt, r[N], n, res = 0;   void Refresh() {     L[0] = cnt = 0;     for (int i = 1; i <= n + 1; i++) L[i] = 10000000;   }   void DFS(int u, int p) {     int Oldval, Oldid, Oldcnt = cnt;     if (cnt == 0 || r[u] > L[cnt])       L[++cnt] = r[u];     else {       Oldid = lower_bound(L, L + n + 1, r[u]) - L;       Oldval = L[Oldid];       L[Oldid] = r[u];     }     res = max(res, cnt);     for (int i = 0; i < a[u].size(); i++) {       int v = a[u][i];       if (v != p) DFS(v, u);     }     if (Oldcnt != cnt)       L[cnt--] = 10000000;     else       L[Oldid] = Oldval;   }   int main() {     ios_base::sync_with_stdio(0);     int u, v;     cin >> n;     for (int i = 1; i <= n; i++) cin >> r[i];     for (int i = 1; i < n; i++) {       cin >> u >> v;       a[u].push_back(v);       a[v].push_back(u);     }     for (int i = 1; i <= n; i++) {       Refresh();       DFS(i, 0);     }     cout << res;     return 0;   }   