#include <bits/stdc++.h>
#define ff first
#define ss second
#define endl '\n'
using namespace std;
const long long INF = (long long) 1e18;
const int mod = (int) 1e9+7;
const int MAXN = (int) 3e5+5;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
ll n;
int joke[MAXN];
vector<int> adj[MAXN];
bool vr[MAXN];
pair<vector<int>, vector<int>> dfs(int v){
vector<pair<int, pair<vector<int>, vector<int>>>> ls, gr;
vector<bool> can(101, 0);
for(int j: adj[v]){
auto c = dfs(j);
if(joke[j] < joke[v]){
ls.push_back({joke[j], c});
}else if(joke[j] > joke[v])
gr.push_back({joke[j], c});
}
sort(ls.begin(), ls.end(), [](auto u, auto v){
return u.ff > v.ff;
});
sort(gr.begin(), gr.end(), [](auto u, auto v){
return u.ff < v.ff;
});
can[joke[v]] = 1;
for(auto &u: ls){
bool cn = 0;
for(auto x: u.ss.ss){
if(x < joke[v] && can[x + 1]){
cn = 1;
break;
}
}
if(cn){
for(auto x: u.ss.ff){
can[x] = 1;
}
}
}
for(auto &u: gr){
bool cn = 0;
for(auto x: u.ss.ff){
if(x > joke[v] && can[x - 1]){
cn = 1;
break;
}
}
if(cn){
for(auto x: u.ss.ss){
can[x] = 1;
}
}
}
vector<int> sl, sg;
for(int i = 1; i <= joke[v]; i++){
if(can[i])
sl.push_back(i);
}
for(int i = joke[v]; i <= 100; i++){
if(can[i])
sg.push_back(i);
}
return make_pair(sl, sg);
}
int main(){
ios_base::sync_with_stdio(false);
cin.tie(nullptr);cout.tie(nullptr);
#ifdef Local
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/int.txt","r",stdin);
freopen("C:/Users/Admin/Desktop/Yazilim/C/IO/out.txt","w",stdout);
#endif
cin>>n;
for(int i = 1; i <= n; i++){
cin>>joke[i];
}
for(int i = 0; i < n - 1; i++){
int a, b;
cin>>a>>b;
adj[a].push_back(b);
}
auto ans = dfs(1);
cout<<(ans.ff.size()) * (ans.ss.size());
#ifdef Local
cout<<endl<<fixed<<setprecision(2)<<1000.0 * clock() / CLOCKS_PER_SEC<< " milliseconds ";
#endif
}
