/*
UID:cheepok
PID:cline
*/

#include<stdio.h>
#include<deque>
#define add(c) c=='L'?q.push_front(t):q.push_back(t)
#define del(c) c=='L'?q.pop_front():q.pop_back()

using namespace std;

deque <int> q;

deque <int> :: iterator it;

int n,t,k;

char c;

int main()
{
	freopen("cline.in","r",stdin);
	freopen("cline.out","w",stdout);
	scanf("%d\n",&n);
	for(int i=1;i<=n;i++){scanf("%c ",&c);
	if(c=='A'){t++;scanf("%c\n",&c);add(c);}
	else{scanf("%c%d\n",&c,&k);while(k--)del(c);}}
	for(it=q.begin();it!=q.end();it++)printf("%d\n",*it);
	return 0;
}