#include <bits/stdc++.h>
using namespace std;
char q[2000005];
int head;
int tail;
int n;
char temp;
char s;
int a;
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		cin>>temp;
		if(temp=='Q'){
			cin>>a;
			cout<<q[head+a]<<endl;
		}
		if(temp=='T'){
			cin>>s;
			q[++tail]=s;
		}
		if(temp=='U'){
			cin>>a;
			if(tail-a>=head)
				tail-=a;
			else
				tail=head;
		}
	}
	return 0;
}

求问QWQ，这道题一开始就没往复杂了想