#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N=100010,mod=1e9+7;
int n,s[N],mk[N],flag,cnt;
int head[N],tot;
ll res;
struct node {
	int v,w,nxt;
}e[N*2];
void add (int u,int v,int w) {
	e[++tot].v=v;
	e[tot].w=w;
	e[tot].nxt=head[u];
	head[u]=tot;
}
void dfs (int u,ll sum,int a,int b,int c) {
	//cout << u <<endl;
	if (a==1&&b==1&&c==1) res+=sum;
	for (int i=head[u];i;i=e[i].nxt) {
		int v=e[i].v,w=e[i].w;
		if (mk[v]==1) continue;
		mk[v]=1;
		if (s[v]==0) dfs(v,(sum+w)%mod,1,b,c);
		else if (s[v]==1) dfs(v,(sum+w)%mod,a,1,c);
		else dfs(v,(sum+w)%mod,a,b,1);
		mk[v]=0;
	}
	return;
}
int main () {
	freopen("blossom.in","r",stdin);
	freopen("blossom.out","w",stdout);
	ios::sync_with_stdio(0);
	cin.tie(0),cout.tie(0);
	cin >> n;
	for (int i=1;i<=n;i++) {
		cin >> s[i];
		if (s[i]==0) flag=i,cnt++;
	}
	for (int i=1;i<n;i++) {
		int a,b,c;
		cin >> a >> b >> c;
		add(a,b,c);
		add(b,a,c);
	}
	if (cnt==1) {
		mk[flag]=1;
    	if (s[flag]==0) dfs(flag,0,1,0,0);
    	else if (s[flag]==1) dfs(flag,0,0,1,0);
    	else dfs(flag,0,0,0,1);
    	mk[flag]=0;
	}else{
		for (int i=1;i<=n;i++) {
    		mk[i]=1;
    		if (s[i]==0) dfs(i,0,1,0,0);
    		else if (s[i]==1) dfs(i,0,0,1,0);
    		else dfs(i,0,0,0,1);
    		mk[i]=0;
		}
    }
 	cout << res/2 <<endl;
	return 0;
}