#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int c(const void* a, const void* b){
	return *(char*)b-*(char*)a;
}
int main()
{
	char a[]={0,0,0,0,0,0,0,0,0,0,0};
	char b[]={0,0,0,0,0,0,0,0,0,0,0};
	scanf("%s%s",a,b);
	qsort(a,11,sizeof(char),c);
	qsort(b,11,sizeof(char),c);
	if(strcmp(a,b)==0)printf("YES\n");
	else printf("NO\n");
	return 0;
}