#include<bits/stdc++.h>
using namespace std;
int a[1000005],ne[1000005];
int idx=1; 
void chushihua()
{
	a[0]=1;
	ne[0]=-1;
}
void charu(int x1,int x2)
{
	a[idx]=x2;
	ne[idx]=ne[x1];
	ne[x1]=idx++;	
}

void chaxun(int x1)
{
	if(ne[x1]==-1){
		cout<<"0"<<endl;
		return ;
	}
	cout<<a[ne[x1]]<<endl;
	
}
void shanchu(int x1)
{
	ne[x1]=ne[ne[x1]]; 
 } 

int main()
{
	int q;
	cin>>q;
	chushihua();
	while(q--)
	{
		int x;
		cin>>x;
		switch(x)
		{
			case 1:
				int x1,x2;
				cin>>x1>>x2;
				charu(x1,x2);
				break;
			case 2:
				cin>>x1;
				chaxun(x1);
				break;	
			case 3:
				cin>>x1;
				shanchu(x1);		
		}
	 } 
	return 0;
}