#include <fstream>
#include <cstdlib>
#include <deque>
using namespace std;
ifstream fin("cline.in");
ofstream fout("cline.out");
string S;
deque <int> Q;
int d,A[1000000],head,tail,L;
void Solve()
{
int i,j,tot=0;deque<int>::iterator it,eit;
	fin>>d;head=1;tail=1;
	fin.get();
	for(i=1;i<=d;i++)
	{
		getline(fin,S);L=S.length();
		if(!((S[0]=='A' && S[1]==' ' && (S[2]=='L' || S[2]=='R') && L==3) || (S[0]=='D' && S[1]==' ' && (S[2]=='L' || S[2]=='R') && S[3]==' ' && (S[4]=='1' || S[4]=='2') && L==5)))
			continue;
		if(S[0]=='A' && S[1]==' ' && S[2]=='L')
			Q.push_front(++tot);
		if(S[0]=='A' && S[1]==' ' && S[2]=='R')
			Q.push_back(++tot);
		if(S[0]=='D' && S[1]==' ' && S[2]=='L')
			for(j=1;j<=S[4]-'0';j++)
				Q.pop_front();
		if(S[0]=='D' && S[1]==' ' && S[2]=='R')
			for(j=1;j<=S[4]-'0';j++)
				Q.pop_back();
	}
	eit=Q.end();
	for(it=Q.begin();it!=eit;it++)
		fout<<*it<<endl;
}

int main()
{
	Solve();
	
	fin.close();
	fout.close();
	return 0;
}