[알고리즘 기초 100제] 29번 음계 (백준 2920)

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

public class _29 {

static void distinc(int arr[], int N) {
		
		boolean aFlag = true;
		boolean bFlag = true;
		
		if(arr[0] != 1) {
			aFlag = false;
		}
		
		for (int i=1; i<arr.length-1; i++) {
			if(arr[i] - arr[i+1] != -1) {
				aFlag = false;
				break;
			}
		}
		
		if(arr[0] != N) {
			bFlag = false;
		}
		
		for (int i=1; i<arr.length-1; i++) {
			if(arr[i] - arr[i+1] != 1) {
				bFlag = false;
				break;
			}
		}
		
		if(aFlag)
			System.out.println("ascending");
		else if(bFlag) {
			System.out.println("descending");
		} else {
			System.out.println("mixed");
		}
}
	
	
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		int N = scan.nextInt();
		
		int[] arr = new int[N];
		
		for(int i=0; i<N; i++) {
			arr[i] = scan.nextInt();
		}
		distinc(arr,N);
	}

}

출력값

4
4 3 2 1
descending