#include<bits/stdc++.h>
  
using namespace std;
  
string s;
  
int a[110],c;
  
char b[350];
  
int main(){
  
	cin>>s;
	for(int i=s.size()-1;i>=0;i--){
		int num=0,tmp=0;
		while(s[i]==')'||s[i]==']'){
			i--;
			num++;
		}
		while(num!=0){
			num--;
			tmp++;
			i--;
			if((s[i+1]=='('&&s[i+1+tmp]==')')||(s[i+1]=='['&&s[i+1+tmp]==']')){
				a[i+1]=1;
				a[i+1+tmp]=1;
			}
			else{
				i++;
				break;
			} 
			tmp++;
		}
	/*	if(s[i]==')'||s[i]==']'){
			int j=i;
			while(s[j]!='('&&s[j]!='['&&j!=0){
				j--;
			}
			if(a[j]!=1){
				if(s[i]==')'&&s[j]=='('){
					a[i]=1;
					a[j]=1;
				}
				if(s[i]==']'&&s[j]=='['){
					a[i]=1;
					a[j]=1;
				}
			}
			
		}*/
	}
	for(int i=0;i<s.size();i++){
		if(a[i]==0){
			if(s[i]=='['){
				b[c]=s[i];
				c++;
				b[c]=']';
				c++;
			}
			if(s[i]==']'){
				b[c]='[';
				c++;
				b[c]=s[i];
				c++;
			}
			if(s[i]=='('){
				b[c]=s[i];
				c++;
				b[c]=')';
				c++;
			}
			if(s[i]==')'){
				b[c]='(';
				c++;
				b[c]=s[i];
				c++;
			}
		}
		else{
			b[c]=s[i];
			c++;
		}
	}
	for(int i=0;i<c;i++){
		cout<<b[i];
	}
}