package main

import (
	"fmt"
	"reflect"
	"sort"
)

func scan() (A string, B string) {
	fmt.Scan(&A)
	fmt.Scan(&B)
	return
}

func strConvertToRune(s string) (r []rune) {
	for _, runeVal := range s {
		r = append(r, runeVal)
	}
	return
}

func main() {
	A, B := scan()
	// A, B := "dog", "god"

	runeA := strConvertToRune(A)
	runeB := strConvertToRune(B)

	sort.Slice(runeA, func(i, j int) bool { return runeA[i] > runeA[j] })
	sort.Slice(runeB, func(i, j int) bool { return runeB[i] > runeB[j] })

	if reflect.DeepEqual(runeA, runeB) {
		fmt.Print("YES")
	} else {
		fmt.Print("NO")
	}
}