#include<bits/stdc++.h>
using namespace std;
struct Node{
 	int data;    
	int nextid; 
}s[1000100];
int main()
{
	s[1].data=1;
	int q,a,x,y;
	cin>>q;
	for(int i=1;i<=q;i++)
	{
		cin>>a;
		if(a==1) cin>>x>>y;
		else cin>>x;
		if(a==1)
		{
			s[x].nextid=y;
			s[y].nextid=-1;
		}
		if(a==2)
			cout<<s[x].nextid<<endl;
		if(a==2&&s[x].nextid==-1) cout<<0<<endl;
		if(a==3) 
		{
			s[x].nextid=s[s[x].nextid].nextid;
		}
	}
	return 0;
}

题目传送门：https://www.luogu.com.cn/problem/B3631