<4.2> 아나그램

일단 코드 먼저 ...

import java.util.Arrays;
import java.util.Scanner;

public class Main {

    public static boolean solution(char[] charArr1, char[] charArr2){
        int[] freq1 = new int[123];
        int[] freq2 = new int[123];


        for(int i=0; i<charArr1.length; i++){
            freq1[charArr1[i]]++;
        }

        for(int i=0; i<charArr2.length; i++){
            freq2[charArr2[i]]++;
        }


        int[] idxArr = new int[122];
        for(int i=0; i<122; i++){
            idxArr[i] = i;
        }

        return Arrays.stream(idxArr)
                .allMatch(i -> freq1[i]==freq2[i]);
    }

    public static void main(String[] args) {

        //0. Scanner 준비
        Scanner sc = new Scanner(System.in);

        //1. 입력
        char[] charArr1 = sc.nextLine().toCharArray();
        char[] charArr2 = sc.nextLine().toCharArray();

        //2. solution() 호출
        boolean isAnagram = solution(charArr1, charArr2);

        //3. 결과 출력
        System.out.println(isAnagram ? "YES" : "NO");
    }
}