#include <iostream>
#include <math.h>
using namespace std;

int main()
{
    int input;
    cin >> input;
    int tmp[64];
    int i = 0;
    bool flag = false;
    tmp[0] = input % 10;
    cout << tmp[0];
    input = floor (input / 10);
    while(input > 10)
    {
        int res = input % 10;
        for(int j = 0 ; j<i+1; j++)
        {
            if(tmp[j] == res)
            {
                flag = true;
            }
        }
        if(false == flag)
        {

            i++;
            tmp[i] = input % 10;
            cout << tmp[i];
        }
        else
        {
            flag = false;
        }
        input = floor (input / 10);
    }
     for(int j = 0 ; j<i+1; j++)
        {
            if(tmp[j] == input)
            {
                flag = true;
            }
        }
    if(flag == false)
    {
        cout << input;
    }

    return 0;
}