[Java] 유쾌한 점퍼 Jolly Jumper

[Java] 유쾌한 점퍼 Jolly Jumper

문제 설명

 

내 코드

import java.io.*;
import java.util.Scanner;
import java.util.Arrays;
import java.lang.Math;

class Main {
   public static void main(String[] args) throws Exception {
      Scanner scanner = new Scanner(System.in);
      
      while (scanner.hasNextInt()){
         
         int n = scanner.nextInt();
         int input []= new int[n];
         int output[] = new int[n-1];

         for (int i =0; i< n; i++){
            input[i] = scanner.nextInt();
            if(i>0)
               output[i-1]= Math.abs(input[i]-input[i-1]);
         }

         Arrays.sort(output);
         String jollystr ="Jolly";

         for(int i=0; i < n-1; i++){
            if( output[i] != i+1 )
               jollystr = "Not jolly";
         }

         System.out.println(jollystr);
      }
      
   }
}

 

 

 

🔑 Key Point 🔑

import java.lang.Math;

Math.abs(-6);  //6이 나옴

import java.util.Arrays;

int [] arr= {1,3,2};
Arrays.sort(arr);  //arr 가 {1,2,3}이 됨

절댓값 함수와 배열 sort 함수 알아두기!