【bzoj3282】Tree

#include<iostream>
#include<cstdio>
#include<cstring>
#include<string>
#include<cmath>
#include<cstdlib>
#include<ctime>
#include<algorithm>
using namespace std;
#define mid ((l+r)>>1)
#define LL long long
#define FILE "dealing"
#define up(i,j,n) for(LL i=(j);i<=(n);i++)
#define pii pair<int,int>
int read(){
	int x=0,f=1,ch=getchar();
	while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
	while(ch>=‘0‘&&ch<=‘9‘)x=(x<<1)+(x<<3)+ch-‘0‘,ch=getchar();
	return f*x;
}
const int maxn=306000,inf=100000000,mod=998244353;
int n,m,cnt;
int c[maxn][2],fa[maxn],rev[maxn],w[maxn],v[maxn],sum[maxn];
void reve(int x){rev[x]^=1,swap(c[x][0],c[x][1]);}
void updata(int x){sum[x]=sum[c[x][1]]^sum[c[x][0]]^v[x];}
void pushdown(int x){if(rev[x])rev[x]^=1,reve(c[x][1]),reve(c[x][0]);}
bool isroot(int x){return c[fa[x]][1]!=x&&c[fa[x]][0]!=x;}
void rotate(int x){
	int y=fa[x],z=fa[y],d=c[y][1]==x;
	if(!isroot(y))c[z][c[z][1]==y]=x;
	fa[y]=x,fa[x]=z,fa[c[x][d^1]]=y;
	c[y][d]=c[x][d^1],c[x][d^1]=y;
	updata(y);updata(x);
}
int q[maxn],top=0;
void splay(int x){
	q[++top]=x;
	for(int i=x;!isroot(i);i=fa[i])q[++top]=fa[i];
	while(top)pushdown(q[top--]);
	while(!isroot(x)){
		int y=fa[x],z=fa[y];
		if(!isroot(y))
			if(c[y][1]==x^c[z][1]==y)rotate(x);
			else rotate(y);
		rotate(x);
	}
}
void access(int x){for(int t=0;x;t=x,x=fa[x])splay(x),c[x][1]=t,updata(x);}
void makeroot(int x){access(x);splay(x);reve(x);}
void link(int x,int y){makeroot(x);fa[x]=y;}
void cut(int x,int y){makeroot(x);access(y);splay(y);if(c[y][0]==x)fa[x]=c[y][0]=0;}
int main(){
	freopen(FILE".in","r",stdin);
	freopen(FILE".out","w",stdout);
	n=read(),m=read();cnt=n;
	up(i,1,n)sum[i]=v[i]=read();
	int ch,x,y;
	while(m--){
		ch=read(),x=read(),y=read();
		if(ch==0){
			makeroot(x),access(y),splay(y);
			printf("%d\n",sum[y]);
		}
		if(ch==1){
			makeroot(x);access(y);splay(y);
			int t=y;while(c[t][0])t=c[t][0];
			if(t!=x)link(x,y);
		}
		if(ch==2)cut(x,y);
		if(ch==3){makeroot(x);v[x]=y;updata(x);}
	}
	return 0;
}