#include<iostream>
#include<cstdio>
#include<cstring>
#include<stack>
using namespace std;
stack <int>num;
stack <char>fff,ans;
char s[20011];
int l;
int main(){
	freopen("passworda.in","r",stdin);
	freopen("passworda.out","w",stdout);
	scanf("%s",s);
	l=strlen(s)-1;
	for(int i=0;i<=l;i++){
		if(isdigit(s[i])){
			int t=0;
			while (isdigit(s[i])){
				t*=10;
				t+=s[i]-'0';
				i++;
			}
			num.push(t);
		}
		if(s[i]!=']')
		fff.push(s[i]);
		else{
			string t1,t2;
			char t3;
			t3=fff.top();
			fff.pop();
			while(t3!='['){
				t2+=t3;
				t3=fff.top();
				fff.pop();
			}
			int n=num.top();
			num.pop();
			for(int j=1;j<=n;j++)
			t1+=t2;
			for(int j=t1.size()-1;j>=0;j--)
			fff.push(t1[j]);
		}
	}
	while(!fff.empty()){
		ans.push(fff.top());
		fff.pop();
	}
	while(!ans.empty()){
		printf("%c",ans.top());
		ans.pop();
	}
	fclose(stdin);
	fclose(stdout);
	return 0;
}