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#include <iostream>
#include <string>
#include <vector>
using namespace std;
int main()
{
string current = "http://www.acm.org/";
vector<string> backward, forward;
while ( true )
{
string c; cin >> c;
bool ignore = false;
if ( c == "BACK" )
{
if ( backward.empty() )
ignore = true;
else
forward.push_back( current ),
current = backward.back(), backward.pop_back();
}
else if ( c == "FORWARD" )
{
if ( forward.empty() )
ignore = true;
else
backward.push_back( current ),
current = forward.back(), forward.pop_back();
}
else if ( c == "VISIT" )
{
backward.push_back( current );
cin >> current;
forward.clear();
}
else if ( c == "QUIT" )
break;
if ( ignore )
cout << "Ignored" << endl;
else
cout << current << endl;
}
return 0;
}