[JAVA-자바] 15686번: 치킨 배달

 

소스코드:

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

public class Main {
    static class Pos {
        private int y;
        private int x;

        Pos(int y, int x) {
            this.y = y;
            this.x = x;
        }
    }

    static BufferedReader br;
    static BufferedWriter bw;

    static int N;
    static int M;
    static int[][] board;

    static List<Pos> homeList;
    static List<Pos> chickenList;

    public static List<List<Pos>> selectChickens() {
        List<List<Pos>> result = new ArrayList<>();
        List<Pos> selected = new ArrayList<>();
        backtracking(0, selected, result);
        return result;
    }

    public static void backtracking(int start, List<Pos> selected, List<List<Pos>> result) {
        if (selected.size() >= 1 && selected.size() <= M) {
            result.add(new ArrayList<>(selected));
        }

        if (selected.size() == M) {
            return;
        }

        for (int i = start; i < chickenList.size(); i++) {
            selected.add(chickenList.get(i));
            backtracking(i + 1, selected, result);
            selected.remove(selected.size() - 1);
        }
    }

    public static int getChickenDistance(List<Pos> selectChickens) {
        int sum = 0;

        for (Pos homePos : homeList) {
            int minDistance = Integer.MAX_VALUE;

            for (Pos chickenPos : selectChickens) {
                int calc = Math.abs(chickenPos.y - homePos.y) + Math.abs(chickenPos.x - homePos.x);
                minDistance = Math.min(minDistance, calc);
            }
            sum += minDistance;
        }

        return sum;
    }

    public static void main(String[] args) throws IOException {
        br = new BufferedReader(new InputStreamReader(System.in));
        bw = new BufferedWriter(new OutputStreamWriter(System.out));

        homeList = new ArrayList<>();
        chickenList = new ArrayList<>();

        StringTokenizer st = new StringTokenizer(br.readLine());
        N = Integer.parseInt(st.nextToken());
        M = Integer.parseInt(st.nextToken());

        board = new int[N + 1][N + 1];

        for (int y = 1; y <= N; y++) {
            st = new StringTokenizer(br.readLine());
            for (int x = 1; x <= N; x++) {
                board[y][x] = Integer.parseInt(st.nextToken());
                if (board[y][x] == 1) {
                    homeList.add(new Pos(y, x));
                } else if (board[y][x] == 2) {
                    chickenList.add(new Pos(y, x));
                }
            }
        }
        br.close();

        int minDistance = Integer.MAX_VALUE;
        for (List<Pos> selectedChickedList : selectChickens()) {
            int calc = getChickenDistance(selectedChickedList);
            minDistance = Math.min(minDistance, calc);
        }

        bw.write(minDistance + "\n");
        bw.close();
    }
}

 

글의 내용 중 잘못된 점이나 수정이 필요한 부분, 혹은 궁금한 사항이 있다면 언제든 댓글로 남겨주시면 감사하겠습니다.

여러분의 피드백은 더 나은 글을 작성하는 데 큰 도움이 됩니다. 감사합니다.