package main

import (
	"fmt"
	"strings"
)

func main() {
	slice := make([]string, 2)
	for i := 0; i < 2; i++ {
		fmt.Scan(&slice[i])
	}

	var strLen int
	diff := false
	strLen = len(slice[0])

	for _, r1 := range slice[0] {
		for i, r2 := range slice[1] {
			// 異なるとき
			if r1 != r2 {
				if strLen == i+1 {
					diff = true
					break
				}
				continue
			}

			// 一致したとき
			slice[0] = strings.Replace(slice[0], string(r1), "", 1)
			slice[1] = strings.Replace(slice[1], string(r2), "", 1)
			strLen--
			break
		}
	}

	if diff {
		fmt.Println("NO")
	} else {
		fmt.Println("YES")
	}
}