#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <functional>
#include <set>
#include <ctime>
#include <random>
using namespace std;
template<typename T> istream& operator >> (istream& is, vector<T>& vec){for(T& val: vec) is >> val; return is;}
template<typename T> istream& operator , (istream& is, T& val){ return is >> val;}
template<typename T> ostream& operator << (ostream& os, const vector<T>& vec){for(int i=0; i<vec.size(); i++) os << vec[i] << (i==vec.size()-1?"\n":" ");return os;}
template<typename T> ostream& operator , (ostream& os, T& val){ return os << " " << val;}
template<typename T> ostream& operator >> (ostream& os, T& val){ return os << " " << val;}

using namespace std;

int main_(){
	int n;
	cin >> n;
	vector<int> a(n);
	cin >> a;

	int max_a = *max_element(a.begin(), a.end());

	vector<vector<int>> G(n);
	for(int i=0; i<n-1; i++){
		int u,v;
		//cin >> u,v;
		scanf("%d%d", &u,&v);
		u--; v--;
		G[u].push_back(v);
		G[v].push_back(u);
	}

	long long ans = 0;

	function<long long (int, int)> dfs = [&](int pos, int last) -> long long{
		vector<long long> dp(max_a+1, 0);
		vector<int> used(max_a+1, 0);

		for(auto& next: G[pos]){
			if(next == last) continue;
			long long tmp = dfs(next, pos);
			dp[a[next]] = max(dp[a[next]], tmp);

			ans = max(ans, dp[a[next]]);

			if(a[pos] != a[next]) used[a[next]] = 1;
		}

		long long ret_small = 0;
		long long cnt_small = 0;
		for(int i=1; i<a[pos]; i++){
			ret_small += dp[i];
			cnt_small += used[i];
		}
		ans = max( ans, ret_small + cnt_small*(cnt_small-1)/2LL );

		long long ret_big = 0;
		long long cnt_big = 0;
		for(int i=a[pos]+1; i<=max_a; i++){
			ret_big += dp[i];
			cnt_big += used[i];
		}
		ans = max(ans, ret_big + cnt_big*(cnt_big-1)/2LL );

		if(last==-1) return 0;
		if(a[pos] == a[last]) return 0;

		long long ret = a[pos]>a[last] ? ret_small : ret_big;
		long long cnt = a[pos]>a[last] ? cnt_small : cnt_big;

		ret -= dp[a[last]];
		cnt -= used[a[last]];
		ret = ret + cnt + cnt*(cnt-1)/2;
		return ret;
	};

	ans = max(ans, dfs(0, -1));
	cout << ans << endl;
	return 0;
}


#include <ctime>
int main(){
	//auto t = clock();
	main_();
	//cerr << (clock()-t) << "[ms]" << endl;
	return 0;
}