#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;
}