#include<bits/stdc++.h>
#define ll long long
#define Mid ll mid = (l + r) >> 1
using namespace std;
const int N = 1e6 + 20;
int n, m, s = 1, L;
ll a[N], b[N];

int rt[N], tot = -1;
struct TREE{
    int lc[N<<5], rc[N<<5], val[N<<5];
	inline void build(int &p, ll l, ll r) {
		p = ++tot;
		val[p] = 0;
		if(l == r) return ;
		Mid;
		build(lc[p], l, mid);
		build(rc[p], mid+1, r);
	}
	inline void add(int pre, int &p, ll l, ll r, ll k) {
		p = ++tot;
		val[p] = val[pre] + 1, lc[p] = lc[pre], rc[p] = rc[pre];
		if(l == r) return ;
		Mid;
		if(k <= mid) add(lc[pre], lc[p], l, mid, k);
		if(k >  mid) add(rc[pre], rc[p], mid+1, r, k);
	}
	inline ll query(ll fa, ll son, ll p1, ll p2, ll l, ll r, ll k) {
		if(l == r) return l;
		Mid;
		ll res1 = val[lc[p1]] + val[lc[p2]] - val[lc[fa]] - val[lc[son]];
		if(k <= res1)   return query(lc[fa], lc[son], lc[p1], lc[p2], l, mid, k);
		if(k >  res1)   return query(rc[fa], rc[son], rc[p1], rc[p2], mid+1, r, k - res1);
	}
}T;

int st[N][22], dep[N];
int cnt = 1, h[N << 1];
struct node{
	ll v, nxt;
}e[N<<1];
void add_edge(ll u, ll v) {
	e[++cnt] = (node){v, h[u]};
	h[u] = cnt;
}
void dfs(ll u, ll pre) {
	dep[u] = dep[pre] + 1;
	st[u][0] = pre;
	T.add(rt[pre], rt[u], 1, L, a[u]);
	for(int i = h[u]; i; i = e[i].nxt) {
		ll v = e[i].v;
		if(v == pre) continue;
		dfs(v, u);
	}
}
void init(){
	for(int i = 1; i <= 20; i++) {
		for(int j = 1; j <= n; j++) {
			st[j][i] = st[st[j][i-1]][i-1];
		}
	}
}
int LCA(int u, int v) {
	if(dep[v] > dep[u]) swap(u, v);
	for(int i = 20; i >= 0; i--) {
		if(dep[st[u][i]] > dep[v]) u = st[u][i];
	}
	if(u == v) return u;
	
	for(int i = 20; i >= 0; i--) {
		if(dep[st[u][i]] !=  dep[st[u][i]]) u = st[u][i], v = st[v][i];
	}
	
	return st[u][0];
}

int main (){
	scanf("%d%d", &n, &m);
	for(int i = 1; i <= n; i++) {
		scanf("%lld", &a[i]);
		b[i] = a[i];
	}
	sort(b + 1, b + n + 1);
	L = unique(b + 1, b + n + 1) - b - 1;
	for(int i = 1; i <= n; i++) {
		a[i] = lower_bound(b + 1, b + L + 1, a[i]) - b;
	}
	
	for(int i = 1; i < n; i++) {
		int u, v;
		scanf("%d%d", &u, &v);
		add_edge(u, v);
		add_edge(v, u);
	}
//	n = L;
	T.build(rt[0], 1, L);
	dfs(s, 0);
	init();
	int last  = 0, u, v, k;
	for(int i = 1; i <= m; i++) {
//		int u, v, k;
		scanf("%d%d%d", &u, &v, &k);
		ll son = LCA(u ^ last, v), fa = st[son][0];
		printf("%d\n", u ^ last);
		last = b[T.query(rt[fa], rt[son], rt[u ^ last], rt[v], 1, L, k)];
		printf("%lld\n", last);
	}
	return 0;
}