#include <bits/stdc++.h>
#define endl '\n'
using namespace std;
typedef long long ll;
void speed()
{
ios_base::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
}
const int maxn = 1e5 + 10;
struct edge
{
int v, u;
edge(int _v = 0, int _u = 0)
{
v = _v;
u = _u;
}
}edges[maxn];
int n, c[maxn];
vector < int > adj[maxn];
void input()
{
cin >> n;
for (int i = 1; i <= n; i ++)
cin >> c[i];
for (int i = 1; i < n; i ++)
{
int v, u;
cin >> v >> u;
adj[v].push_back(u);
edges[i] = edge(v, u);
}
}
int sub[maxn], depth[maxn], heavy[maxn], par[maxn];
void calc(int v)
{
heavy[v] = -1;
sub[v] = 1;
for (int u : adj[v])
{
par[u] = v;
depth[u] = depth[v] + 1;
calc(u);
sub[v] += sub[u];
if (heavy[v] == -1 || sub[u] > sub[heavy[v]])
heavy[v] = u;
}
}
int cidx[maxn], chead[maxn], cpos[maxn];
vector < int > chain[maxn];
int csz = 1;
void hld(int v, int head)
{
cidx[v] = csz;
chead[v] = head;
chain[cidx[v]].push_back(v);
if (v == head)
cpos[v] = 1;
else
cpos[v] = cpos[par[v]] + 1;
if (heavy[v] != -1)
hld(heavy[v], head);
for (int u : adj[v])
{
if (u == heavy[v])
continue;
csz ++;
hld(u, u);
}
}
set < pair < int, int > > range[maxn];
vector < pair < int, int > > get_path_values(int v)
{
vector < pair < int, int > > path;
while(v != 0)
{
int d = cpos[v];
while(d > 0)
{
set < pair < int, int > > :: iterator it = range[cidx[v]].lower_bound({d, n + 1});
/**for (pair < int, int > cur : range[cidx[v]])
cout << cur.first << " " << cur.second << endl;
cout << d << endl;*/
it = prev(it);
path.push_back({d - it -> first + 1, c[chain[cidx[v]][it -> second - 1]]});
d = it -> first - 1;
}
v = par[chead[v]];
}
reverse(path.begin(), path.end());
return path;
}
void clear_path(int v)
{
int col = c[v];
range[cidx[v]].clear();
range[cidx[v]].insert({1, cpos[v]});
///cout << "here " << 1 << " " << cpos[v] << endl;
v = par[chead[v]];
while(v != 0)
{
///cout << "back " << v << endl;
int d = cpos[v];
///cout << "cidx " << cidx[v] << " " << d << endl;
set < pair < int, int > > :: iterator it = range[cidx[v]].lower_bound({d, n + 1});
it = prev(it);
///cout << it -> first << " " << it -> second << endl;
pair < int, int > nw = {d + 1, it -> second};
range[cidx[v]].erase(it);
range[cidx[v]].insert(nw);
while(true)
{
set < pair < int, int > > :: iterator it = range[cidx[v]].lower_bound({d, n + 1});
if (it == range[cidx[v]].begin())
{
///cout << it -> first << " --- " << it -> second << endl;
break;
}
it = prev(it);
range[cidx[v]].erase(it);
}
range[cidx[v]].insert({1, d});
c[v] = col;
v = par[chead[v]];
}
}
ll fen[maxn];
void update(int pos, ll val)
{
for (int i = pos; i <= n; i += (i & -i))
fen[i] += val;
}
ll query(int pos)
{
ll s = 0;
for (int i = pos; i > 0; i -= (i & -i))
s += fen[i];
return s;
}
void find_inversions(vector < pair < int, int > > &path)
{
ll ans = 0;
int sz = path.size();
for (int i = sz - 1; i >= 0; i --)
{
ans = ans + query(path[i].second - 1) * (ll)(path[i].first);
update(path[i].second, path[i].first);
}
for (int i = 0; i < sz; i ++)
update(path[i].second, -path[i].first);
/**for (int i = 0; i < sz; i ++)
for (int j = i + 1; j < sz; j ++)
{
if (path[i].second > path[j].second)
{
ans = ans + (ll)(path[i].first) * (ll)(path[j].first);
}
}*/
cout << ans << endl;
}
void simulate()
{
//for (int i = 1; i <= n; i ++)
//cout << i << " : " << cidx[i] << " " << cpos[i] << " " << heavy[i] << " " << sub[i] << endl;
//exit(0);
range[cidx[1]].insert({1, 1});
for (int i = 1; i < n; i ++)
{
///cout << "pass " << i << endl;
vector < pair < int, int > > path = get_path_values(edges[i].v);
//cout << "survive " << i << endl;
//cout << "inversions ";
find_inversions(path);
//cout << "path " << endl;
//for (pair < int, int > cur : path)
//cout << cur.first << " " << cur.second << endl;
//cout << "path" << endl;
//for (pair <int, int > cur : path)
// cout << cur.first << " " << cur.second << endl;
clear_path(edges[i].u);
/**cout << "edge " << i << endl;
for (int i = 1; i <= csz; i ++)
{
cout << "chain " << i << endl;
for (pair < int, int > cur : range[i])
cout << cur.first << " " << cur.second << endl;
}
if (i == 4)
break;*/
}
}
void compress_data()
{
vector < int > d;
for (int i = 1; i <= n; i ++)
d.push_back(c[i]);
sort(d.begin(), d.end());
unordered_map < int, int > mp;
for (int i = 0; i < n; i ++)
mp[d[i]] = i + 1;
for (int i = 1; i <= n; i ++)
c[i] = mp[c[i]];
}
void solve()
{
input();
compress_data();
calc(1);
hld(1, 1);
simulate();
}
int main()
{
speed();
solve();
return 0;
}
