RT 不知道为啥有一行格式炸了

#include <iostream>
#include <cstdio>
#include <algorithm>
const int N = 3e5+5;
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*10+ch-'0';
		ch = getchar();
	}
	return x*f;
}
struct aa{
	int nums;
	int ch[2];
}node[N*35*2]; 
int tot;
int qzh[N];
int root[N];
void add(int u,int v,int rk,int x){//u依附历史版本v 
	if(rk<0){
		return;
	}
	int num = (x>>rk)&1;
	node[u].ch[!num] = node[v].ch[!num];
	node[u].ch[num] = ++tot;
	node[node[u].ch[num]].nums = node[node[v].ch[num]].nums+1;
	add(node[u].ch[num],node[v].ch[num],rk-1,x);
	return;
}
int query(int u,int v,int rk,int x){
	if(rk<0){
		return 0;
	}
	int num = (x>>rk)&1;
	if(node[node[v].ch[!num]].nums>node[node[u].ch[!num]].nums){
		return (1<<rk)+query(node[u].ch[!num],node[v].ch[!num],rk-1,x);
	}else{
		return query(node[u].ch[num],node[v].ch[num],rk-1,x);
	} 
}
using namespace std;
int main(){
	int n,m,x,y,z;
	char opt[5];
	n = read();m = read();
	root[0] = ++tot;
	add(root[0],0,25,0);
	for(int i=1;i<=n;i++){
		x = read();
		qzh[i] = (qzh[i-1] ^ x);
		root[i] = ++tot;
		add(root[i],root[i-1],25,qzh[i]);
	}
	for(int i=1;i<=m;i++){
		scanf("%s",opt);
		if(opt[0]=='A'){
			x = read();
			n++;
			root[n] = ++tot;
			qzh[n] = (qzh[n-1]^x);
			add(root[n],root[n-1],25,qzh[n]);
		}else{
			x = read();y = read();z = read();
			cout<<query(x-1==0?0:root[x-2],root[y-1],25,z^qzh[n])<<'\n';
		}
	}
	return 0;
}
/*
5 5
2 6 4 3 6
A 1 
Q 3 5 4 
A 4
Q 5 7 0 
Q 3 6 6 
*/