[코드업/자바] 1805 - 입체기동장치 생산공장

import java.util.*;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        List<Device> devices = new ArrayList<>();
        int n = sc.nextInt();
        for(int i=0; i<n; i++){
            Device d = new Device(sc.nextInt(), sc.nextInt());
            devices.add(d);
        }
        sc.close();
        
        Collections.sort(devices);
        for(Device d : devices){
            System.out.println(d.id + " " + d.gas);
        }
    }
}

class Device implements Comparable<Device> {
    private int id;
    private int gas;

    Device(int id, int gas){
        this.id = id;
        this.gas = gas;
    }

    public int compareTo(Device d){
        return id - d.id;
    }
}

Comparable, compareTo로 정렬

---

import java.util.*;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        List<Device> devices = new ArrayList<>();
        int n = sc.nextInt();
        for(int i=0; i<n; i++){
            Device d = new Device(sc.nextInt(), sc.nextInt());
            devices.add(d);
        }
        sc.close();

        devices = devices.stream().sorted((e2, e1) -> e2.id - e1.id).collect(Collectors.toList());

        for(Device d : devices){
            System.out.println(d.id + " " + d.gas);
        }
    }
}

class Device {
    int id;
    int gas;

    Device(int id, int gas){
        this.id = id;
        this.gas = gas;
    }
}

stream으로 정렬

---

import java.util.*;
import java.util.stream.Collectors;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        List<Device> devices = new ArrayList<>();
        int n = sc.nextInt();
        for(int i=0; i<n; i++){
            Device d = new Device(sc.nextInt(), sc.nextInt());
            devices.add(d);
        }
        sc.close();

        String output = devices
                .stream()
                .sorted(Comparator.comparingInt(Device::getId))
                .map(e -> "%d %d".formatted(e.getId(), e.getGas()))
                        .collect(Collectors.joining("\n"));

        System.out.println(output);
    }
}

class Device {
    private int id;
    private int gas;

    Device(int id, int gas){
        this.id = id;
        this.gas = gas;
    }

    public int getId() {
        return id;
    }

    public int getGas() {
        return gas;
    }
}

stream 바로 출력