#include<algorithm>
#include<iostream>
#include<fstream>
#include<string>
using namespace std;
ifstream fin("passworda.in");
ofstream fout("passworda.out");
int n;
int f[30000]={0};
int t[10000]={0};
string s;
void tryy(int l,int r)
{
    int i=l,j=0;
    while (i<r)
	{
        while (s[i]-'A'<26 && s[i]-'A'>=0)
		{
            fout<<s[i];
            i++;
        }
        if (s[i]=='[')
		{
            j=i;
            int g=0;
            while (s[++i]-'0'<10 && s[i]-'0'>=0)
                g=g*10+s[i]-'0';
            for (;g>0;g--)
                tryy(i,f[j]-1);
            i=f[j]+1;
        }
    }
}
int main()
{
    fin>>s;
    int tou=0;
    for (int i=0;i<s.size();i++)
	{
        if (s[i]=='[') t[++tou]=i;
        if (s[i]==']') f[t[tou--]]=i;
    }
    tryy(0,s.size()-1);
	fin.close();
	fout.close();
    return 0;
}