#include<iostream>
using namespace std;
char s[20000];
int p=0;
int m(int k){
    char h;
    int len=0;
    while((h=getchar())!=']'){
        if(h=='[')len+=m(getchar()-'0');
        else{
            s[p++]=h;
            len++;
        }
    }
    for(int i=1;i<k;i++)
        for(int j=0;j<len;j++)
            s[p++]=s[p-len];
    return len*k;
}
int main(){
    char x;
    s[0]=1;
    while((x=getchar())!='\n'){
        if(x=='['){
            int len=0;
            while((x=getchar())!=']'){
                if(x=='[')len+=m(getchar()-'0');
                else{
                    s[p++]=x;
                    len++;
                }
            }
            for(int i=1;i<=s[0]-'0';i++)
                for(int j=1;j<len;j++)
                    cout<<s[j];
        }
        if(x==']')continue;
        cout<<x;
    }
    return 0;
}