RT，全 RE 喜提 $0\text{pts}$.

RE 信息是：invalid memory reference.

数组已经开得很大了/kk，求大佬查错/kk.

$\textbf{Code:}$

#include<bits/stdc++.h>
using namespace std;
#define debug(a, n)\
	printf(#a ":");\
	for(int i = 1; i <= n; ++i) cout << a[i] << ' ';\
	cout << '\n';
inline int read(){
    int x = 0, f = 1;
    char ch = getchar();
    while(ch < '0' || ch > '9') { if(ch == '-') f = -1; ch = getchar(); }
    while(ch >= '0' && ch <= '9') { x = (x << 1) + (x << 3) + (ch ^ 48); ch = getchar();}
    return x * f;
//	int x;
//	scanf("%d", &x);
//	return x;
}
const int N = 1e6 + 10;
const int T = 2e7 + 10;
int n, q, val[N];
vector<int> g[N << 1];
int ch[T][2], siz[T], tot, totd/*in dfs*/, L[N], R[N], dep[N], fa[25][N];
int type1[N], type2[N];
void cop(int x, int y) {
	ch[x][0] = ch[y][0];
	ch[x][1] = ch[y][1];
	siz[x] = siz[y];
}
void Insert(int &rt, int x, int Bit) {
	++tot;
	cop(tot, rt); rt = tot;
	++siz[rt];
	if(Bit >= 0) {
		int turn = ((x >> Bit) & 1);
		Insert(ch[rt][turn], x, Bit - 1);
	}
}
void dfs(int x, int from) {
	++totd;
	fa[0][x] = from;
	dep[x] = dep[fa[0][x]] + 1;
	L[x] = totd;
	type1[totd] = type1[totd - 1]; /*dfn*/
	Insert(type1[totd], val[x], 29);
	type2[x] = type2[from];       /*paths*/
	Insert(type2[x], val[x], 29);
	for(int t = 1; (1 << t) < dep[x] && t <= 20; ++t) {
		fa[t][x] = fa[t - 1][fa[t - 1][x]];
	}
	for(int y : g[x]) {
		if(y == from) continue;
		dfs(y, x);
	}
	R[x] = totd;
}
int lca(int x, int y) {
	if(dep[x] < dep[y]) swap(x, y);
	for(int i = 20, d = dep[x] - dep[y]; i >= 0; --i) {
		if(d <= 0) break;
		int ups = (1 << i);
		while(d >= ups) {
			x = fa[i][x];
			d -= ups;
		}
	}
	if(x == y) {
		return x;
	}
	for(int i = 20; i >= 0; --i) {
		if(!fa[i][x] || !fa[i][y] || fa[i][x] == fa[i][y]) continue;
		x = fa[i][x]; y = fa[i][y];
	}
	return fa[x][0];
}
int query(int lp, int rp, int x, int Bit) {
	if(Bit <= 0) return 0;
	int turn = ((x >> Bit) & 1) ^ 1;
//	cout << turn << endl;
	if(siz[ch[lp][turn]] > siz[ch[rp][turn]]) {
//		puts("abc"); 
		return query(ch[lp][turn], ch[rp][turn], x, Bit - 1) | (1 << Bit);
	}
	else {
//		puts("xyz");
		turn = 1 - turn;
		return query(ch[lp][turn], ch[rp][turn], x, Bit - 1);
	}
} 
int main() {
	n = read(); q = read();
	for(int i = 1; i <= n; ++i) val[i] = read();
	for(int i = 1; i < n; ++i) {
		int _u, _v;
		_u = read();
		_v = read();
		g[_u].push_back(_v);
		g[_v].push_back(_u);
	}
	dfs(1, 0);
//	debug(dep, n);
//	debug(L, n);
//	debug(R, n);
//	debug(val, n);
//	debug(siz, n);
	while(q --){
		int opt, x, y, z;
		opt = read(); x = read(); y = read();
		if(opt == 1) {
			printf("%d\n", query(type1[R[x]], type1[L[x] - 1], y, 29));
		}
		else {
			z = read();
			int father = lca(x, y);
			father = fa[0][father];
			int res1 = query(type2[x], type2[father], z, 29);
			int res2 = query(type2[y], type2[father], z, 29);
			printf("%d\n", max(res1, res2));
		}
	}
	return 0;
}