#include <bits/stdc++.h>
using namespace std;
typedef unsigned long long ull;
int n, m, B;
int dfx = 0, dfn[200010], rnk[200010], siz[200010], c[200010];
ull a[200010], ans[200010], f[200010], tg[510];
struct Tree{
	int hd[200010], e[400010][2], fa[200010], dep[200010], Fa[200010][19];
	int b[200010];
	void dfs1(int u){
		int i, v;
		for(i = 1, Fa[u][0] = fa[u]; i <= 18; i++) Fa[u][i] = Fa[Fa[u][i - 1]][i - 1];
		for(i = hd[u]; i > 0; i = e[i][0]){
			v = e[i][1];
			if(v != fa[u]){
				fa[v] = u; dep[v] = dep[u] + 1; dfs1(v);
			}
		}
	}
	void dfs2(int u){
		dfn[u] = ++dfx; rnk[dfx] = u; siz[u] = 1;
		int i, v;
		for(i = hd[u]; i > 0; i = e[i][0]){
			v = e[i][1];
			if(v != fa[u]){
				dfs2(v);
				siz[u] += siz[v];
			}
		}
	}
	void dfs4(int u, int x){
		b[u] = x;
		int i, v;
		for(i = hd[u]; i > 0; i = e[i][0]){
			v = e[i][1];
			if(v != fa[u] && b[v] == 0) dfs4(v, x);
		}
	} 
	int dfs3(int u){
		int i, v, x = 0;
		for(i = hd[u]; i > 0; i = e[i][0]){
			v = e[i][1];
			if(v != fa[u]){
				x = max(x, dfs3(v) + 1);
			}
		}
		if(x >= B || u == 1){ dfs4(u, u); return -1; }
		else return x;
	}
	void dfs5(int u){
		int i, v;
		for(i = hd[u]; i > 0; i = e[i][0]){
			v = e[i][1];
			if(v != fa[u]){
				c[v] += c[u]; dfs5(v);
			}
		}
	}
	void init(bool fl){
		int i, u, v;
		for(i = 1; i <= n; i++) hd[i] = 0, b[i] = 0;
		for(i = 1; i >> 1 < n - 1; i++){
			scanf("%d%d", &u, &v);
			e[i][0] = hd[u]; e[i][1] = v; hd[u] = i;
			i++;
			e[i][0] = hd[v]; e[i][1] = u; hd[v] = i;
		}
		fa[1] = 1; dep[1] = 0; dfs1(1);
		if(fl){
			for(i = 1; i <= n; i++) b[i] = (i + B - 1) / B;
		}
	}
	int lca(int u, int v){
		if(dep[u] < dep[v]) swap(u, v);
		int i, j = dep[u] - dep[v];
		for(i = 0; 1 << i <= j; i++){
			if(j >> i & 1) u = Fa[u][i];
		}
		if(u == v) return u;
		for(i = 18; i >= 0; i--){
			if(Fa[u][i] != Fa[v][i]) u = Fa[u][i], v = Fa[v][i];
		}
		return fa[u];
	}
} T1, T2;
int qry2(int x){ return (x > 0 ? f[x] + tg[T1.b[x]] : 0); }
int qry(int u){ return qry2(dfn[u] + siz[u] - 1) - qry2(dfn[u] - 1); }
void upd(int u, ull x){
	u = dfn[u];
	int i;
	for(i = u; i <= n && T1.b[i] == T1.b[u]; i++) f[i] += x;
	for(i = T1.b[u] + 1; i <= T1.b[n]; i++) tg[i] += x;
}
ull calc(int u){
	ull res = 0;
	while(u != T2.b[u]){
		res += qry(u); u = T2.fa[u];
	}
	return res;
}
struct Node{
	int u, v, w1, w2; ull k;
} q[200010];
int main()
{
	int i, j, u, v, w;
	ull x;
	scanf("%d%d", &n, &m); B = sqrt(n);
	for(i = 1; i <= n; i++){
		scanf("%llu", &a[i]); f[i] = 0;
	}
	T1.init(1); T2.init(0);
	T1.dfs2(1); T2.dfs3(1);
	for(i = 1; i <= m; i++){
		scanf("%d%d%llu", &q[i].u, &q[i].v, &q[i].k); ans[i] = 0;
		q[i].w1 = T1.lca(q[i].u, q[i].v); q[i].w2 = T2.lca(q[i].u, q[i].v);
	}
	for(i = 1; i <= n; i++){
		if(T2.b[i] == i){
			x = 0;
			for(u = 1; u <= n; u++) c[u] = 0;
			for(u = i; 1; u = T2.fa[u]){
				c[u]++; x += a[u];
				if(u == 1) break;
			}
			T1.dfs5(1);
			for(j = 1; j <= m; j++){
				u = q[j].u; v = q[j].v; w = q[j].w1;
				x += (c[u] + c[v] - c[w] - (w > 1 ? c[T1.fa[w]] : 0)) * q[j].k;
				w = q[j].w2;
				if(i == T2.b[u]) ans[j] += x;
				if(i == T2.b[v]) ans[j] += x;
				if(i == T2.b[w]) ans[j] -= x;
				if(w > 1 && i == T2.b[T2.fa[w]]) ans[j] -= x;
			}
		}
	}
	for(i = 1; i <= T1.b[n]; i++) tg[i] = 0;
	for(i = 1; i <= n; i++){
		upd(i, a[i]);
		if(i > 1) upd(T1.fa[i], -a[i]);
	}
	for(i = 1; i <= m; i++){
		u = q[i].u; v = q[i].v; w = q[i].w1; x = q[i].k;
		upd(u, x); upd(v, x); upd(w, -x);
		if(w > 1) upd(T1.fa[w], -x);
		w = q[i].w2;
		ans[i] += calc(u) + calc(v) - calc(w) - (w > 1 ? calc(T2.fa[w]) : 0llu);
		printf("%llu\n", ans[i]);
	}
	return 0;
}