#include <iostream>
#include <set>

using namespace std;

int main()
{
    int n;
    while(cin>>n)
    {
        set<int>s;
        while(n)
        {
            int temp = n%10;
            if(s.find(temp)==s.end())
            {
                cout<<temp;
            }
            n/=10;
            s.insert(temp);
        }
        cout<<endl;
    }
}