#include<iostream>
#include<cstring>
using namespace std;
int main()
{
	char command[8],url[101][75]={"http://www.acm.org/"};
	int k=0,n;
	while(cin>>command)
	{
		if(command[0]=='Q')
			break;
		else if(command[0]=='V')
		{
			k++;
			cin>>url[k];
			cout<<url[k]<<endl;
			n=k;
		}
		else if(command[0]=='B')
		{
			k--;
			if(k<0)
			{
				cout<<"Ignored\n";
				k=0;
			}
			else
				cout<<url[k]<<endl;
		}
		else
		{
			k++;
			if(k>n)
			{
				cout<<"Ignored\n";
				k=n;
			}
			else
				cout<<url[k]<<endl;
		}
	}
	return 0;
}

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