#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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