/*
 *                                                     __----~~~~~~~~~~~------___
 *                                    .  .   ~~//====......          __--~ ~~
 *                    -.            \_|//     |||\\  ~~~~~~::::... /~
 *                 ___-==_       _-~o~  \/    |||  \\            _/~~-
 *         __---~~~.==~||\=_    -_--~/_-~|-   |\\   \\        _/~
 *     _-~~     .=~    |  \\-_    '-~7  /-   /  ||    \      /
 *   .~       .~       |   \\ -_    /  /-   /   ||      \   /
 *  /  ____  /         |     \\ ~-_/  /|- _/   .||       \ /
 *  |~~    ~~|--~~~~--_ \     ~==-/   | \~--===~~        .\
 *           '         ~-|      /|    |-~\~~       __--~~
 *                       |-~~-_/ |    |   ~\_   _-~            /\
 *                            /  \     \__   \/~                \__
 *                        _--~ _/ | .-~~____--~-/                  ~~==.
 *                       ((->/~   '.|||' -_|    ~~-/ ,              . _||
 *                                  -_     ~\      ~~---l__i__i__i--~~_/
 *                                  _-~-__   ~)  \--______________--~~
 *                                //.-~~~-~_--~- |-------~~~~~~~~
 *                                       //.-~~~--\
 *                       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *                               神兽保佑            永无BUG
 */

/*
 * @Description: I want to be the weakest vegetable in the world!
 * @Author: I.Z.
*/
#include<bits/stdc++.h>
using namespace std;
#define MOD         998244353
#define speMOD      2933256077ll
#define pii         pair<int,int>
#define all(v)      v.begin(),v.end()
#define pb          push_back
#define REP(i,b,e)  for(int i=(b);i<(int)(e);++i)
#define over(x)     {cout<<(x)<<endl;return;}
#define lowbit(x)   ((x)&(-(x)))
#define cntbit(x)   __builtin_popcount(x)
#define deal(v)     sort(all(v));v.erase(unique(v.begin(),v.end()),v.end())
#define lbound(v,x) lower_bound(all(v),x)-v.begin()
//mt19937 sd(random_device{}());
mt19937 sd(20090419);
int qpow(int a,int b,int m=MOD,int res=1){
	a%=m;
	while(b>0)res=(b&1)?(res*a%m):(res),a=a*a%m,b>>=1;
	return res;
}
int exgcd(int x,int y,int &a,int &b){
	if(y==0){
		a=1;b=0;
		return x;
	}
	int d=exgcd(y,x%y,a,b);
	int z=b;
	b=a-b*(x/y);
	a=z;
	return d;
}
int _x_,_y_;
inline int inverse(int x,int y=MOD){
	exgcd(x,y,_x_,_y_);
	return (_x_+y)%y;
}
int fac[2000005],inv[2000005];
void init(int n){
	fac[0]=inv[0]=1;
	REP(i,1,n+1)fac[i]=fac[i-1]*i%MOD;
	inv[n]=qpow(fac[n],MOD-2);
	for(int i=n-1;i>=1;--i)inv[i]=inv[i+1]*(i+1)%MOD;
}
int binom(int x,int y){
	return x<y||y<0? 0:fac[x]*inv[y]%MOD*inv[x-y]%MOD;
}
#define ull unsigned long long
int read(){
	int res=0;char c=getchar();
	while(c<48||c>57)c=getchar();
	do res=(res<<1)+(res<<3)+(c^48),c=getchar();while(c>=48&&c<=57);
	return res;
}
ull readll(){
	ull res=0;char c=getchar();
	while(c<48||c>57)c=getchar();
	do res=(res<<1)+(res<<3)+(c^48),c=getchar();while(c>=48&&c<=57);
	return res;
}
struct query{
	int x,y,l1,l2;ull k;
}qr[200005];
int n,q;
vector<int>v1[200005],v2[200005];
struct BIT{
	ull a[200005],b[200005];
	int B;
	void init(){
		REP(i,0,n+1)a[i]=0;
		B=sqrt(n);
	}
	void add(int l,int r,ull x){
//		cout<<'+'<<l<<' '<<r<<' '<<x<<endl;
		//l+x r+1-x
		if(l/B==r/B){REP(i,l,r+1)a[i]+=x;return;}
		REP(i,l,(l/B+1)*B)a[i]+=x;
		REP(i,r/B*B,r+1)a[i]+=x;
		REP(i,l/B+1,r/B)b[i]+=x;
//		++l;r+=2;
//		while(l<=n)a[l]+=x,l+=lowbit(l);
//		while(r<=n)a[r]-=x,r+=lowbit(r);
	}
	ull query(int x){
		return a[x]+b[x/B];
//		++x;ull ans=0;
//		while(x)ans+=a[x],x-=lowbit(x);
//		return ans;
	}
}ds2;
int B;
struct ds_tree1{
	int tp[200005],fa[200005],sz[200005],dep[200005],ms[200005],tot,dfn[200005],rev[200005];
	int cnt[200005];
	void dfs0(int x,int pre,int d){
		dep[x]=d;fa[x]=pre;sz[x]=1;ms[x]=-1;int maxn=0;
		for(auto i:v1[x])if(i!=pre){
			dfs0(i,x,d+1);
			sz[x]+=sz[i];
			if(maxn<sz[i])maxn=sz[i],ms[x]=i;
		}
	}
	void dfs1(int x,int pre,int t){
		tp[x]=t;rev[tot]=x;dfn[x]=tot++;
		if(ms[x]!=-1)dfs1(ms[x],x,t);
		for(auto i:v1[x])if(i!=pre&&i!=ms[x])dfs1(i,x,i);
	}
	void build(){
		tot=0;dfs0(0,-1,0);
		dfs1(0,-1,0);
	}
	int getlca(int x,int y){
		while(tp[x]!=tp[y]){
			if(dep[tp[x]]<dep[tp[y]])y=fa[tp[y]];
			else x=fa[tp[x]];
		}
		return dep[x]<dep[y]? x:y;
	}
	void update(query a){
		int x=a.x,y=a.y;
		while(tp[x]!=tp[y]){
//			cout<<x<<' '<<y<<endl;
			if(dep[tp[y]]>dep[tp[x]])swap(x,y);
			ds2.add(dfn[tp[x]],dfn[x],a.k);
			x=fa[tp[x]];
		}
		if(dep[x]>dep[y])swap(x,y);
		ds2.add(dfn[x],dfn[y],a.k);
	}
	void dfs2(int x,int pre){
		for(auto i:v1[x])if(i!=pre)cnt[i]+=cnt[x],dfs2(i,x);
	}
	void rebuild(){
		REP(i,1,n)cnt[rev[i]]+=cnt[fa[rev[i]]];
	}
	ull ask(query a){
		return (cnt[a.x]+cnt[a.y]-cnt[a.l1]-(a.l1?cnt[fa[a.l1]]:0))*a.k;
	}
	ull asker(int x){return ds2.query(dfn[x]);}
}ds1;
ull a[200005];
int b[200005],sp[200005],tp[200005],dep[200005],fa[200005],dn[200005],tot;
int id[200005],rid[200005];
int an[200005][20];
ull ans[200005];
void add(int x,int id,int op){
//	cout<<x<<' '<<id<<' '<<op<<' '<<ds1.asker(x)<<endl;
	while(x!=tp[x]){
		ans[id]+=ds1.asker(x)*op;
		x=fa[x];
	}
}
void predfs(int x,int pre){
	dn[tot++]=x;
	for(auto i:v2[x])if(i!=pre)predfs(i,x);
}
void dfst2(int x,int pre,int d){
	dep[x]=d;fa[x]=pre;an[x][0]=pre;
	REP(i,0,19)if(an[x][i]==-1)an[x][i+1]=-1;else an[x][i+1]=an[an[x][i]][i];
	if(sp[x])tp[x]=x;else tp[x]=tp[fa[x]];
	for(auto i:v2[x])if(i!=pre)dfst2(i,x,d+1);
}
int getlca(int x,int y){
	if(dep[x]<dep[y])swap(x,y);
	int d=dep[x]-dep[y];
	REP(i,0,19)if((d>>i)&1)x=an[x][i];
	if(x==y)return x;
	for(int i=18;i>=0;--i)if(an[x][i]!=-1&&an[y][i]!=an[x][i])x=an[x][i],y=an[y][i];
	return fa[x];
}
void Main() {
	n=read();q=read();
	REP(i,0,n)a[i]=readll();
	REP(i,1,n){
		int x=read()-1,y=read()-1;
		v1[x].pb(y);v1[y].pb(x);
	}
	REP(i,1,n){
		int x=read()-1,y=read()-1;
		v2[x].pb(y);v2[y].pb(x);
	}
	B=300;
	uniform_int_distribution<int>rd(1,n-1);
	sp[0]=1;
	REP(i,1,n)id[i]=-1;
	predfs(0,-1);
	REP(i,1,B){
		int x=dn[n/B*i];
		sp[x]=1;id[x]=i;rid[i]=x;
	}
	dfst2(0,-1,0);ds1.build();
//	REP(i,0,n){
//		int x=i,cnt=0;
//		while(x!=tp[x])++cnt,x=fa[x];
//		cerr<<cnt<<' ';
//	}
//	cerr<<endl;
	cerr<<clock()<<endl;
	REP(i,0,q){
		int x=read()-1,y=read()-1;ull z=readll();
		int l2=getlca(x,y);
		if(x==l2)swap(x,y);
		qr[i]={x,y,ds1.getlca(x,y),l2,z};
	}
	cerr<<clock()<<endl;
	int T=0;
	REP(i,0,B){
		int x=rid[i];
		REP(j,0,n)ds1.cnt[j]=0;
		do ++ds1.cnt[x],x=fa[x];while(x!=-1);
		ull cur=0;
		REP(j,0,n)if(ds1.cnt[j])cur+=a[j];
		T-=clock();ds1.rebuild();T+=clock();
		REP(j,0,q){
			cur+=ds1.ask(qr[j]);
			if(tp[qr[j].x]==rid[i])ans[j]+=cur;
			if(qr[j].y!=qr[j].l2&&tp[qr[j].y]==rid[i])ans[j]+=cur;
			if(qr[j].y!=qr[j].l2&&tp[qr[j].l2]==rid[i])ans[j]-=cur;
			if(qr[j].l2&&tp[fa[qr[j].l2]]==rid[i])ans[j]-=cur;
		}
	}
	cerr<<T<<endl;
	cerr<<clock()<<endl;
//	REP(i,0,q)cout<<ans[i]<<' ';
//	cout<<endl;
	ds2.init();
	REP(i,0,n)ds2.add(ds1.dfn[i],ds1.dfn[i],a[i]);
	REP(i,0,q){
		ds1.update(qr[i]);
		add(qr[i].x,i,1);
		if(qr[i].y!=qr[i].l2)add(qr[i].y,i,1);
		if(qr[i].y!=qr[i].l2)add(qr[i].l2,i,-1);
		if(qr[i].l2)add(fa[qr[i].l2],i,-1);
	}
	REP(i,0,q)cout<<ans[i]<<"\n";
}
void TC() {
    int tc=1;
	while(tc--){
		Main();
		cout.flush();
	}
	cerr<<clock()<<endl;
}
signed main() {
	return cin.tie(0),cout.tie(0),ios::sync_with_stdio(0),TC(),0;
}
/*
1. CLEAR the arrays (ESPECIALLY multitests)
2. DELETE useless output
 */