#include <cstdio>
#include <cstring>
using namespace std;
int main() {
char arr[21];
int len;
int minCnt;
int nums[26];
while(EOF != scanf("%s", arr)) {
getchar();
minCnt = 100;
memset(nums, 0, sizeof(nums));
len = strlen(arr);
for(int i = 0; i < len; i++) {
nums[arr[i] - 'a']++;
}
for(int i = 0; i < 26; i++) {
if(nums[i] != 0 && nums[i] < minCnt) {
minCnt = nums[i];
}
}
for(int i = 0; i < len; i++) {
if(nums[arr[i] - 'a'] != minCnt) {
printf("%c", arr[i]);
}
}
printf("\n");
}
return 0;
}