#include<stdio.h>
#include<stdlib.h>
#include<ctype.h>

int main(){
     char s1[20], s2[20];
     scanf("%s", s1);
     scanf("%s", s2);
     if(strlen(s1) < 1 || strlen(s1) > 10 || strlen(s2) < 1 || strlen(s2) > 10){
         printf("Invalid input");
         return 0;
     }
     for(int i = 0; s1[i]; i++)
          if(!isalpha(s1[i])){
         printf("Invalid input"); return 0; return 0;}
         for(int i = 0; s2[i]; i++)
            if(!isalpha(s2[i]))
            
        {printf("Invalid input");return 0;}
        if(strlen(s1) != strlen(s2)){
            printf("No");
            return 0;
        }
        for(int i = 0; i < strlen(s1) - 1; i++)
         for(int j = i + 1; j < strlen(s1); j++){
             if(s1[i] > s1[j]){char
    t = s1[i]; s1[i] = s1[j]; s1[j]=t;}
             if(s2[i] > s2[j]){char
    t = s2[i]; s2[i] = s2[j]; s2[j]=t; }
             
         }
         if(strcmp(s1,s2) == 0)
           printf("YES");
           else printf("NO");
           return 0;
}