[백준 1758] 알바생 강호 (Java)

1. 오름차순 정렬

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.Arrays;
 
public class Main{
    public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        
        int n = Integer.parseInt(br.readLine());
        int[] arr = new int[n];  // 입력받을 배열 선언
 
        // 금액 입력받기
        for(int i=0; i<n; i++){
            arr[i] = Integer.parseInt(br.readLine());
        }
 
        Arrays.sort(arr);
 
        long ans=0; // 최종값이 int형 범위를 넘어갈 수 있으므로 long으로 선언
 
        for(int i=n-1, k=0; i>=0; i--, k++){
            if(arr[i]-k > 0){
                ans+=(arr[i]-k);
            } 
        }
 
        System.out.println(ans);
    }
}

 

 

2. 내림차순 정렬

 

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;
 
public class Main{public static void main(String[] args) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        
        int n = Integer.parseInt(br.readLine());
        Integer[] arr = new Integer[n];  // 참조로 
 
        for(int i=0; i<n; i++){
            arr[i] = Integer.parseInt(br.readLine());
        }
 
        Arrays.sort(arr,Collections.reverseOrder());
 
        long ans=0;
        for(int i=0; i<n; i++){
            if(arr[i]-i > 0){
                ans+=(arr[i]-i);
            } 
        }
        System.out.println(ans);
    }
}