// Make the best become better
// No room for laziness
#include<bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
using namespace std;
using ll = long long;
using ld = long double;
using ull = unsigned long long;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
const int maxN = 1e4 + 5;
const int maxV = 105;
const int mod = 1e9 + 7;
const ll oo = 1e18;
int n;
int a[maxN];
vector<int> adj[maxN];
int deg[maxN];
int root;
bitset<maxV> bs[maxN][maxV];
bitset<maxV> f[maxV];
void ReadInput()
{
cin >> n;
for(int i=1; i<=n; i++)
cin >> a[i];
for(int i=1; i<n; i++)
{
int u, v;
cin >> u >> v;
adj[u].pb(v);
deg[v]++;
}
}
void dfs(int u)
{
for(int v : adj[u])
{
dfs(v);
}
for(int i=1; i<=100; i++)
f[i].reset();
f[a[u]][a[u]] = 1;
for(int v : adj[u])
{
for(int l=1; l<=100; l++)
f[l] |= bs[v][l];
}
for(int l=1; l<=100; l++)
for(int r=l; r<=100; r++)
if(f[l][r])
f[l] |= f[r + 1];
for(int l=1; l<=100; l++)
for(int r=l; r<=100; r++)
{
if(l > a[u] || r < a[u])
continue;
if(l == a[u] && f[a[u] + 1][r]) bs[u][l][r] = 1;
if(r == a[u] && f[l][a[u] - 1]) bs[u][l][r] = 1;
if(f[l][a[u] - 1] & f[a[u] + 1][r]) bs[u][l][r] = 1;
}
bs[u][a[u]][a[u]] = 1;
}
void Solve()
{
dfs(1);
int res = 0;
for(int l=1; l<=100; l++)
for(int r=l; r<=100; r++)
res += bs[1][l][r];
// cout << bs[1][1][3];return;
cout << res;
}
int32_t main()
{
// freopen("x.inp", "r", stdin);
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
ReadInput();
Solve();
}
