#include<bits/stdc++.h>
int main()
{
	int i=21;
	char st[21];
	memset(st,false,sizeof(st));
	scanf("%s",&st);
	for(;i--;){
		if(st[i]){
			if(isalnum(st[i]) || isalpha(st[i])){
				printf("%c",st[i]);
			}
	}
	printf("\n");
	return 0;
}
}
