#include<iostream>

 #include<cstring>

 using namespace std;

 #define maxn 100006

 char s[maxn];

 int nex[maxn], n;

 int main() {

     while (cin >> s + ) {

         int cur = , last = ;

         nex[] = ;

         char ch;

         for (int i = ; i <=strlen(s + ); i++) {

             ch = s[i];

             if (ch == '[') cur = ;

             else if (ch == ']') cur = last;

             else {

                 nex[i] = nex[cur];

                 nex[cur] = i;

                 if (cur == last)last = i;

                 cur = i;

             }

         }

         for (int i = nex[]; i != ; i = nex[i])

             cout << s[i];

         cout << endl;

     }

     return ;

 }