#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int, int>
#define f first
#define s second
#define all(v) v.begin(), v.end()
#define pb push_back
const int BIG = 1e9 + 10;
#define int ll
struct DSU
{
vector<int> p;
vector<int> mx;
void init(int n)
{
p.resize(n);
mx.resize(n);
for (int i = 0; i < n; ++i)
p[i] = i;
}
int getR(int v)
{
return p[v] == v ? v : p[v] = getR(p[v]);
}
void merge(int x, int y)
{
x = getR(x);
y = getR(y);
if (x == y)
return;
if (mx[x] > mx[y])
swap(x, y);
p[x] = y;
}
};
struct test
{
vector<vector<int>> tree, jump;
vector<int> d, tin, tout;
int timer = 0;
void precalc(int v, int pr = -1)
{
tin[v] = ++timer;
for (auto tov : tree[v])
if (tov != pr)
{
d[tov] = d[v] + 1;
jump[tov][0] = v;
for (int i = 1; i < 20; ++i)
{
jump[tov][i] = jump[jump[tov][i - 1]][i - 1];
}
precalc(tov, v);
}
tout[v] = ++timer;
}
bool isParent(int x, int y)
{
return tin[x] <= tin[y] and tout[y] <= tout[x];
}
int lca(int x, int y)
{
if (isParent(x, y))
return x;
if (isParent(y, x))
return y;
for (int i = 19; i >= 0; --i)
if (!isParent(jump[x][i], y))
x = jump[x][y];
return jump[x][0];
}
int getD(int x, int y)
{
return d[x] + d[y] - 2 * d[lca(x, y)];
}
void solve()
{
int n;
cin >> n;
tree.resize(n);
jump.resize(n, vector<int>(20));
d.resize(n);
tin.resize(n);
tout.resize(n);
vector<pii> els;
vector<int> a(n);
for (int i = 0; i < n; ++i)
{
int x;
cin >> x;
els.pb({x, i});
a[i] = x;
}
sort(all(els));
tree.resize(n);
for (int i = 1; i < n; ++i)
{
int x, y;
cin >> x >> y;
--x, --y;
tree[x].pb(y);
tree[y].pb(x);
}
precalc(0);
vector<int> res(n);
DSU dsu;
dsu.init(n);
for (int i = 0; i < n; ++i)
dsu.mx[i] = a[i];
for (auto [val, v] : els)
{
int curMx = 0;
for (auto tov : tree[v])
if (a[tov] < a[v])
{
int nextV = dsu.getR(tov);
curMx = max(curMx, res[nextV] + getD(nextV, v));
}
res[v] = curMx;
for (auto tov : tree[v])
if (a[tov] < a[v])
{
dsu.merge(v, tov);
}
if (val == n)
cout << res[v] << "\n";
}
}
};
main()
{
test t;
t.solve();
}
