#include <stdio.h>
#include <stdint.h>
void remove_duplicates(char *str) {
if (str==NULL) return;
int res[256]={0};
int j = 0;
for (int i = 0; str[i] != '\0'; i++) {
unsigned char val = (unsigned char) str[i];
if (res[val]==0){
res[val]=1;
str[j] = str[i];
j++;
}
}
str[j] = '\0';
}
int main() {
char str[101];
fgets(str, sizeof(str), stdin);
// Remove newline
uint8_t i = 0;
while (str[i]) {
if (str[i] == '\n') {
str[i] = '\0';
break;
}
i++;
}
remove_duplicates(str);
printf("%s", str);
return 0;
}