TheWireUs-Day5

#include <bits/stdc++.h>
#define ll long long
using namespace std;

int main()
{
    string s;
    cin >> s;
    stack<char> st;
    for (ll i = 0; i < s.length(); i++)
    {
        if (st.empty() || st.top() != s[i])
        {
            st.push(s[i]);
            cout << s[i];
        }
        else
        {
            cout << "*";
        }
    }

    return 0;
}