#include <bits/stdc++.h>

                                            //    #include <boost/multiprecision/cpp_int.hpp>
 
                               	       #define int long long
                                                #define inf  1000000007
                                              #define pa pair<int,int>
                                               #define pad pair<double,double>
                                                #define ll long long
                                                #define pal pair<double,double>
                                                #define ppap pair<pa,int>
                                          #define PI 3.14159265358979323846
                                                #define paa pair<pa,pa>
                                                #define  mp make_pair
                                                #define  pb push_back
                                                #define EPS (1e-10)
                                                #define equals(a,b) (fabs((a)-(b))<EPS)
                                            //    #define double long double
        int dx[4]={0,-1,0,1};
        int dy[4]={1,0,-1,0};
                                                using namespace std;
                                       			class pa3{
                                                	public:
                                                	int x,y,z;
                                                	pa3(int x=0,int y=0,int z=0):x(x),y(y),z(z) {}
                                                	bool operator < (const pa3 &p) const{
                                                		if(x!=p.x) return x<p.x;
                                                		if(y!=p.y) return y<p.y;
                                                		 return z<p.z;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                       				bool operator > (const pa3 &p) const{
                                                		if(x!=p.x) return x>p.x;
                                                		if(y!=p.y) return y>p.y;
                                                		 return z>p.z;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const pa3 &p) const{
                                                		return x==p.x && y==p.y && z==p.z;
                                                	}
                                                		bool operator != (const pa3 &p) const{
                                                			return !( x==p.x && y==p.y && z==p.z);
                                                	}
                                                
                                                };
                                                
                                                class pa4{
                                                	public:
                                                	int x;
                                                	int y,z,w;
                                                	pa4(int x=0,int y=0,int z=0,int w=0):x(x),y(y),z(z),w(w) {}
                                                	bool operator < (const pa4 &p) const{
                                                		if(x!=p.x) return x<p.x;
                                                		if(y!=p.y) return y<p.y;
                                                		if(z!=p.z)return z<p.z;
                                                		return w<p.w;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator > (const pa4 &p) const{
                                                		if(x!=p.x) return x>p.x;
                                                		if(y!=p.y) return y>p.y;
                                                		if(z!=p.z)return z>p.z;
                                                		return w>p.w;
                                                		//return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const pa4 &p) const{
                                                		return x==p.x && y==p.y && z==p.z &&w==p.w;
                                                	}
                                                	
                                                	bool operator != (const pa4 &p) const{
                                                		return !(x==p.x && y==p.y && z==p.z &&w==p.w);
                                                	}
                                                		
                                                
                                                };
                                                class pa2{
                                                	public:
                                                	int x,y;
                                                	pa2(int x=0,int y=0):x(x),y(y) {}
                                                	pa2 operator + (pa2 p) {return pa2(x+p.x,y+p.y);}
                                                	pa2 operator - (pa2 p) {return pa2(x-p.x,y-p.y);}
                                                	bool operator < (const pa2 &p) const{
                                                		return x!= p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator > (const pa2 &p) const{
                                                		return x != p.x ? x>p.x: y>p.y;
                                                	}
                                                	bool operator == (const pa2 &p) const{
                                                		return abs(x-p.x)==0 && abs(y-p.y)==0;
                                                	}
                                                	bool operator != (const pa2 &p) const{
                                                		return !(abs(x-p.x)==0 && abs(y-p.y)==0);
                                                	}
                                                		
                                                
                                                };
                                                
                                              
                                                
                                                       #define ppa pair<int,pas>
                                                class Point{
                                                	public:
                                                	double x,y;
                                                	Point(double x=0,double y=0):x(x),y(y) {}
                                                	Point operator + (Point p) {return Point(x+p.x,y+p.y);}
                                                	Point operator - (Point p) {return Point(x-p.x,y-p.y);}
                                                	Point operator * (double a) {return Point(x*a,y*a);}
                                                	Point operator / (double a) {return Point(x/a,y/a);}
                                                	double absv() {return sqrt(norm());}
                                                	double norm() {return x*x+y*y;}
                                                	bool operator < (const Point &p) const{
                                                		return x != p.x ? x<p.x: y<p.y;
                                                	}
                                                	bool operator == (const Point &p) const{
                                                		return fabs(x-p.x)<EPS && fabs(y-p.y)<EPS;
                                                	}
                                                };
                                                typedef Point Vector;
                                         #define pl pair<int,pas>
                                                struct Segment{
                                                Point p1,p2;
                                                };
                                                 double dot(Vector a,Vector b){
                                                	return a.x*b.x+a.y*b.y;
                                                }
                                                double cross(Vector a,Vector b){
                                                	return a.x*b.y-a.y*b.x;
                                                }
                                            
                    bool parareru(Point a,Point b,Point c,Point d){
                    //	if(abs(cross(a-b,d-c))<EPS)cout<<"dd "<<cross(a-b,d-c)<<endl;
                    	return abs(cross(a-b,d-c))<EPS;
                    }
                    double distance_ls_p(Point a, Point b, Point c) {
                      if ( dot(b-a, c-a) < EPS ) return (c-a).absv();
                      if ( dot(a-b, c-b) < EPS ) return (c-b).absv();
                      return abs(cross(b-a, c-a)) / (b-a).absv();
                    }
                    bool is_intersected_ls(Segment a,Segment b) {
                    	if(a.p1==b.p1||a.p2==b.p1||a.p1==b.p2||a.p2==b.p2) return 1;
                    	if(parareru((a.p2),(a.p1),(a.p1),(b.p2))&&parareru((a.p2),(a.p1),(a.p1),(b.p1))){
                    //		cout<<"sss"<<endl;
                    		if(dot(a.p1-b.p1,a.p1-b.p2)<EPS) return true;
                    		if(dot(a.p2-b.p1,a.p2-b.p2)<EPS) return true;
                    		if(dot(a.p1-b.p1,a.p2-b.p1)<EPS) return true;
                    		if(dot(a.p1-b.p2,a.p2-b.p2)<EPS) return true;
                    		return false;
                    	}
                      else return ( cross(a.p2-a.p1, b.p1-a.p1) * cross(a.p2-a.p1, b.p2-a.p1) < EPS ) && ( cross(b.p2-b.p1, a.p1-b.p1) * cross(b.p2-b.p1, a.p2-b.p1) < EPS );
                    }
                     
                    double segment_dis(Segment a,Segment b){
                    	if(is_intersected_ls(a,b))return 0;
                    	double r=distance_ls_p(a.p1, a.p2, b.p1);
                    	r=min(r,distance_ls_p(a.p1, a.p2, b.p2));
                    	r=min(r,distance_ls_p(b.p1, b.p2, a.p2));
                    	r=min(r,distance_ls_p(b.p1, b.p2, a.p1));
                    	return r;
                    }
                    Point intersection_ls(Segment a, Segment b) {
                      Point ba = b.p2-b.p1;
                      double d1 = abs(cross(ba, a.p1-b.p1));
                      double d2 = abs(cross(ba, a.p2-b.p1));
                      double t = d1 / (d1 + d2);
                     
                      return a.p1 + (a.p2-a.p1) * t;
                    }
                     
                                    string itos( int i ) {
                                    ostringstream s ;
                                    s << i ;
                                    return s.str() ;
                                    }
                                     
                                    int gcd(int v,int b){
                                    	if(v==0) return b;
                                    	if(v>b) return gcd(b,v);
                                    	if(v==b) return b;
                                    	if(b%v==0) return v;
                                    	return gcd(v,b%v);
                                    }
                     
                                    double distans(double x1,double y1,double x2,double y2){
                                    	double rr=(x1-x2)*(x1-x2)+(y1-y2)*(y1-y2);
                                    	return sqrt(rr);
                                    	
                                    }
                                                        /*
        double bekid(double w,int r){
        	if(r==0) return 1.0;
        	if(r==1) return w;
        	if(r%2) return bekid(w,r-1)*w;
        	double f=bekid(w,r/2);
        	return f*f;
        }*/
                                    int mod;
                    int beki(int wa,int rr,int warukazu){
                    	if(rr==0) return 1%warukazu;
                    	if(rr==1) return wa%warukazu;
                    	if(rr%2==1) return (beki(wa,rr-1,warukazu)*wa)%warukazu;
                    	int zx=beki(wa,rr/2,warukazu);
                    	return (zx*zx)%warukazu;
                    }
                          /*          
                    int pr[401000];
                    int inv[401000];
                   
                   

                  
        			int comb(int nn,int rr){
        				int r=pr[nn]*inv[rr];
        				r%=mod;
        				r*=inv[nn-rr];
        				r%=mod;
        				
        				return r;
        			}
                  
                    void gya(int ert){
                    	pr[0]=1;
                    	for(int i=1;i<ert;i++){
                    		pr[i]=(pr[i-1]*i)%mod;
                    	}
                    	for(int i=0;i<ert;i++) inv[i]=beki(pr[i],mod-2,mod);
                    	
                    }
                    */
                    
                  //   cin.tie(0);
        		//	ios::sync_with_stdio(false);
        			//priority_queue<pa3,vector<pa3>,greater<pa3>> pq;            
                     //sort(ve.begin(),ve.end(),greater<int>());

struct segsum{
	//       1
	//   2        3
	// 4   5   6    7
	
	
	private:
	public:
	
	// 1<<10 = 1024
	// 1<<11 = 2048
	// 1<<12 = 4096
	// 1<<13 = 8192
	// 1<<14 = 16384
	// 1<<15 = 32768
	// 1<<16 = 65536
	// 1<<17 = 131072
	// 1<<18 = 262144
	
	int cor=(1<<18);
	
	vector<int> vec;

	
	void shoki1(){
		vec.resize(2*cor+3, 0);
	}
		void shoki2(){
			for(int i=cor-1;i>0;i--) vec[i]=vec[2*i]+vec[2*i+1];
		}
			void clear(){
		    
	    	for(int i=0;i<(int)vec.size();i++)vec[i]=0;
    	}
	void updadd(int x,int w){
		//x 項目に w加算
		x+=cor;
		vec[x]+=w;
		while(1){
			x/=2;
			if(x==0) break;
			vec[x]=vec[2*x]+vec[2*x+1];
		}
		
	}
	
	void updchan(int x,int w){
		//x項目をwに変更
		x+=cor;
		vec[x]=w;
		while(1){
			x/=2;
			if(x==0) break;
			vec[x]=vec[2*x]+vec[2*x+1];
		}
		
	}
	// [a,b)
	// k-th node
	// k no kukanha [l,r)
	int sum(int a,int b,int k=1,int l=0,int r=-10){
		if(r<0)r=cor;
		
	//	cout<<a<<" "<<b<<" "<<k<<" "<<l<<" "<<r<<endl;
		
		if(a<=l && r<=b){
			return vec[k];
		}
		if(r<=a || b<=l){
			return 0;
		}
		
		int v1=sum(a,b,k*2,l,(l+r)/2),v2=sum(a,b,k*2+1,(l+r)/2,r);
		return v1+v2;
	}
	
};
segsum ss;

int v[100020];

int dp[100020][20];
int depth[100020];
vector<int> G[100020],G2[100020];

void dfss(int r,int p,int d){
	dp[r][0]=p;
	depth[r]=d;
	for(auto v:G[r])if(v!=p){
		dfss(v,r,d+1);
		G2[r].pb(v);
	}
}

int lca(int a,int b){
	if(depth[a]<depth[b])swap(a,b);
	int sa=depth[a]-depth[b];
	
	for(int r=19;r>=0;r--)if(sa&(1<<r))a=dp[a][r];
	
	if(a==b)return a;
	
	for(int r=19;r>=0;r--)if(dp[a][r]!=dp[b][r]){
		a=dp[a][r],b=dp[b][r];
	}
	return dp[a][0];
}

int iti[100020][2];
int cnt=0;

void dfs2(int r){
	iti[r][0]=cnt;
	cnt++;
	for(auto v:G2[r])dfs2(v);
	iti[r][1]=cnt;
	cnt++;
}
int gya[100020];
set<int> se;
map<int,int>ma;

queue<pa3> qu[100020];
int ans[100020];
int val(int a,int b){
	if(a==b) return ss.vec[ss.cor+iti[a][0]];
	int lc=lca(a,b);
//	cout<<"lca "<<a<<" "<<b<<" "<<lc<<endl;
	if(lc==a){
		 return ss.sum(iti[a][0],iti[b][0]+1);
	}
	if(lc==b){
		 return ss.sum(iti[b][0],iti[a][0]+1);
	}
	return ss.sum(iti[lc][0],iti[b][0]+1)+ss.sum(iti[lc][0],iti[a][0]+1)-ss.vec[ss.cor+iti[lc][0]];
}
int l[100020];

int c[100020][2];

vector<int> ve[100020];
  signed main(){
 	              cin.tie(0);
   		ios::sync_with_stdio(false);
  	
int n,q;
  	
  	cin>>n>>q;
  	for(int i=1;i<=n;i++){
  		cin>>v[i];
  		se.insert(v[i]);
  	}
  	cnt=1;
  	for(auto it=se.begin();it!=se.end();it++){
  		ma[*it]=cnt;
  		gya[cnt]=*it;
  		cnt++;
  	}
  	for(int i=1;i<=n;i++){
  		v[i]=ma[v[i]];
  	//	cout<<v[i]<<endl;
  		ve[v[i]].pb(i);
  	}
  		for(int i=0;i<n-1;i++){
  		int y,yy;
  		cin>>y>>yy;
  		G[y].pb(yy);
  		G[yy].pb(y);
  	}
  	dfss(1,1,0);
  	for(int r=1;r<=19;r++)for(int i=1;i<=n;i++){
  		dp[i][r]=dp[dp[i][r-1]][r-1];
  	}
  	cnt=0;
  	dfs2(1);
  	ss.shoki1();
  	
  	
  	for(int i=0;i<q;i++){
  		
  		cin>>c[i][0]>>c[i][1]>>l[i];
  		int me=(100010)/2;
  			qu[me].push((pa3){0,100010,i});
  	}
  	int qw=0;
  	int q2=q;
  	while(1){
  	//	cout<<q<<endl;
  		ss.clear();
  		for(int i=0;i<100012;i++){
  			for(auto w:ve[i]){
  				ss.updadd(iti[w][0],1);
  				ss.updadd(iti[w][1],-1);
  			}
  			while(qu[i].size()){
  			//	cout<<i<<endl;
  				qw++;
  			//	if(qw>200)exit(0);
  			pa3 z=qu[i].front();
  			qu[i].pop();
  			int si,ue;
  		//		cout<<z.z<<" "<<i<<" "<<l[z.z]<<" "<<val(c[z.z][0],c[z.z][1])<<endl;
  			if(val(c[z.z][0],c[z.z][1])>=l[z.z]){
  				si=z.x;
  				ue=i;
  				if(ue-si<=1){
  				ans[z.z]=ue;
  					q--;
  				}
  				else{
  				//cout<<si<<" "<<ue<<endl;
  					qu[(ue+si)/2].push((pa3){si,ue,z.z});
  				}
  			}
  			else{
  				si=i;
  				ue=z.y;
  				if(ue-si<=1){
  				ans[z.z]=ue;
  					q--;
  				}
  				else{
  				//cout<<si<<" "<<ue<<endl;
  					qu[(ue+si)/2].push((pa3){si,ue,z.z});
  				}
  			}
  			}
  			
  		}
  		if(q==0){
  		//	cout<<"owa"<<endl;
  			break;
  		}
  	}
  	
  	for(int i=0;i<q2;i++)cout<<gya[ans[i]]<<endl;
  	

  	return 0;
               }
                
                
                





Measured memory_bytes: 130148