#include<stdio.h>
#include<string.h>
#include<math.h>
int main()
{
char in[100] = { 0 }, out[100] = { 0 }; int k = 0;
gets(in);
for (int i = 0; i < strlen(in); i++)
{
int found = 0;
for (int j = 0; j < strlen(out); j++)
{
if (out[j] == in[i])
{
found = 1;
break;
}
}
if (found == 0)
{
out[k++] = in[i];
}
else
{
continue;
}
}
puts(out);
return 0;
}