#include<bits/stdc++.h>
using namespace std;
string expand(){
	string s="",x;
	char c;int d;
	while(cin>>c){
		if(c=='['){
			cin>>d;
			x=expand();
			while(d--) s+=x;
		}else if(c==']')return s;
		else s+=c;
	}
	return s;
}
int main(){
	cout<<expand();
	return 0;
}