#include<iostream>
#include<cstdio>
#include<cstring>
#define syy myson
using namespace std;
int len,i=0;
char word[20010];
string ans="";
string work()
{
	string fuck="";
	int numx=0;
	while(word[i]>='0'&&word[i]<='9')
	{
		numx=numx*10+int(word[i])-48;
		i++;
	}
	while(word[i]!=']')
	{
		if(word[i]!='[')
		{
			fuck+=word[i];
			i++;
		}
		else
		{
			i++;
			fuck+=work();		
		}
	}
	i++;
	string shit=fuck;
	while(numx>1)
	{
		fuck+=shit;
		numx--;
	}
	return fuck;
}
int Main()
{
	freopen("passworda.in","r",stdin);freopen("passworda.out","w",stdout);
	ios::sync_with_stdio(false);
	cin>>word;
	len=strlen(word);
	while(i<len)
	{
		if(word[i]!='[')
		{
			ans+=word[i];
			i++;
		}
		else
		{
			i++;
			ans+=work();
		}
	}
	cout<<ans;
	return 0;
}
int main(){;};
int syy=Main();