#include <stdio.h>
#include <stdint.h>
void remove_duplicates(char *str) {
unsigned int asciiTable[128] = {0};
int idx=0,newIdx=0;
while(*(str+idx)!='\0'){
char carac = *(str+idx);
(asciiTable[carac])++;
if((asciiTable[carac])==1) *(str+newIdx)=carac,newIdx++;
idx++;
}
*(str+newIdx)='\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;
}