#include <iostream>
#include <cstring>
using namespace std;
int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    string s;
    cin >> s;
    int pos;
    string ss;
    while ((pos = s.rfind('[')) != string::npos) {
        ss = "";
        for (int i = pos + 2;; ++i) {
            if (s[i] == ']')
                break;
            ss += s[i];
        }
        int num = int (s[pos + 1] - '0');
        for (;;) {
            s.erase(pos, 1);
            if (s[pos] == ']') {
                s.erase(pos, 1);
                break;
            }
        }
        for (int k = 0; k < num; ++k)
            s.insert(pos, ss);
    }
    cout << s;
    return 0;
}