#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define endl '\n'

int main(){
	ios::sync_with_stdio(false); cin.tie(0);

	int n;
	cin >> n;

	const int N = 2*n + 1;

	vector<vector<int>> f(N);
	for(int i=2; i<N; i++){
		for(int j=2; j<N; j++){
			if(gcd(i, j) > 1) f[i].push_back(j);
		}
	}

	vector<int> arr(n);
	for(auto &d : arr) cin >> d;
	vector<vector<int>> adj(n);
	for(int i=1; i<n; i++){
		int a, b;
		cin >> a >> b;
		a--, b--;
		adj[a].push_back(b);
		adj[b].push_back(a);
	}
	const int INF = 1e9;
	vector<vector<int>> dp(n, vector<int>(N, -1));
	function<void(int, int)> dfs = [&](int u, int par){
		for(int c : adj[u]){
			if(c == par) continue;
			dfs(c, u);
		}
		for(int i=2; i<N; i++){
			dp[u][i] = arr[u] == i ? 0 : i;
			for(int c : adj[u]){
				if(c == par) continue;
				int mnC = INF;
				for(int j : f[i]){
					if(dp[c][j] != -1) mnC = min(mnC, dp[c][j]);
				}
				if(mnC == INF){
					dp[u][i] = -1;
					break;
				}
				dp[u][i] += mnC;
				if(dp[u][i] > 2*n){
					dp[u][i] = -1;
					break;
				}
			}
			if(dp[u][i] > 2*n){
				dp[u][i] = -1;
				break;
			}
		}
	};
	dfs(0, -1);	
	int res = INF;
	for(int i=2; i<N; i++){
		if(dp[0][i] != -1) res = min(res, dp[0][i]);
	}
	assert(res != INF);
	cout << res;
}
// gcc a.cpp -std=gnu++14 -o a.exe
// g++ a.cpp -g -O2 -std=gnu++14 -static -o a.exe