#include<bits/stdc++.h>
#define int long long
using namespace std;
auto read = [](){
	int x;
	scanf("%lld", &x);
	return x;
};
const int N = 2005;
int n, a[N], d[N], f[N], ans;
vector<int> v[N];
void build(int x, int fa){
	for(int i = 0; i < v[x].size(); i ++){
		int y = v[x][i];
		if(y == fa)
		continue;
		d[y] = d[x] + 1;
		build(y, x);
	}
	return;
}
void dfs(int x){
	f[x] ++;
	for(int i = 0; i < v[x].size(); i ++){
		int y = v[x][i];
		if(d[y] < d[x] || a[y] <= a[x])
		continue;
		dfs(y);
		f[x] += f[y];
	}
	for(int i = 0; i < v[x].size(); i ++){
		int y = v[x][i];
		if(d[y] < d[x] || a[y] <= a[x])
		continue;
		ans += f[y];
		for(int j = i + 1; j < v[x].size(); j ++){
			int z = v[x][j];
			if(d[z] < d[x] || a[z] <= a[x])
			continue;
			ans += f[y] * f[z];
		}
	}
	return;
}
signed main(){
	freopen("touch.in", "r", stdin);
	freopen("touch.out", "w", stdout);
	n = read();
	for(int i = 1; i <= n; i ++)
	a[i] = read();
	for(int i = 1, x, y; i < n; i ++){
		x = read(), y = read();
		v[x].push_back(y), v[y].push_back(x);
	}
	build(1, 0);
	for(int i = 1; i <= n; i ++){
		if(f[i] == 0)
		dfs(i);
	}
	printf("%lld", ans);
	return 0;
}