#include <stack>
#include <iostream>
using namespace std;


class Decoding{

   public:
       string decodingUtil(string str);
       stack<int> integerstack;
       stack<char> stringstack;
       string temp = "", result = "";





};
// Returns decoded string for 'str'
string decode(string str)
{
    stack<int> integerstack;
    stack<char> stringstack;
    string temp = "", result = "";
    int i = 0;
    // Traversing the string
    while( i < str.length() )
    {

        int count = 0;

        // If number, convert it into number
        // and push it into integerstack.
        if (str[i] >= '0' && str[i] <='9')
        {
            while (str[i] >= '0' && str[i] <= '9')
            {
                count = count * 10 + str[i] - '0';
                i++;
            }

            i--;
            integerstack.push(count);
        }

        // If closing bracket ']', pop elemment until
        // '[' opening bracket is not found in the
        // character stack.
        else if (str[i] == ')')
        {
            temp = "";
            count = 0;

            if (! integerstack.empty())
            {
                count = integerstack.top();
                integerstack.pop();
            }

            while (! stringstack.empty() && stringstack.top()!='(' )
            {
                temp = stringstack.top() + temp;
                stringstack.pop();
            }

            if (! stringstack.empty() && stringstack.top() == '(')
                stringstack.pop();

            // Repeating the popped string 'temo' count
            // number of times.
            for (int j = 0; j < count; j++)
                result = result + temp;

            // Push it in the character stack.
            for (int j = 0; j < result.length(); j++)
                stringstack.push(result[j]);

            result = "";
        }

        // If '[' opening bracket, push it into character stack.
        else if (str[i] == '(')
        {
            if (str[i-1] >= '0' && str[i-1] <= '9')
                stringstack.push(str[i]);

            else
            {
                stringstack.push(str[i]);
                integerstack.push(1);
            }
        }

        else
            stringstack.push(str[i]);
            i++;
    }

    // Pop all the elmenet, make a string and return.
    while (! stringstack.empty())
    {
        result = stringstack.top() + result;
        stringstack.pop();
    }

    return result;
}

// Driven Program
int main()
{
    string str;
    cout << "Enter a desired string: " << endl;
    cin >> str;
    cout << decode(str) << endl;
    return 0;
}