BAEK_17135_캐슬디펜스

11 Oct 2019 in Sidemenu / BaekJoon

https://www.acmicpc.net/problem/17135

17135. 캐슬디펜스

import java.io.*;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.PriorityQueue;
import java.util.StringTokenizer;

public class Main_17135_캐슬디펜스 {
	static int N, M, D, maxkill = Integer.MIN_VALUE;
	static int[][] map;

	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new FileReader("res/Main_17135_캐슬디펜스.txt"));
//		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine());
		N = Integer.parseInt(st.nextToken());
		M = Integer.parseInt(st.nextToken());
		D = Integer.parseInt(st.nextToken());
		map = new int[N + 1][M];
		for (int i = 0; i < N; i++) {
			st = new StringTokenizer(br.readLine());
			for (int j = 0; j < M; j++) {
				map[i][j] = Integer.parseInt(st.nextToken());
			}
		}
		putArcher(0, 0);
		System.out.println(maxkill);
	}

	private static void putArcher(int cnt, int idx) {
		if (cnt == 3) {
			shootEnemy();
			return;
		}
		for (int i = idx; i < M; i++) {
			map[N][i] = 2;
			putArcher(cnt + 1, i + 1);
			map[N][i] = 0;
		}
	}

	private static void shootEnemy() {
		int killcnt = 0;
		int[][] newmap = new int[N + 1][M];
		for (int i = 0; i < N + 1; i++) {
			for (int j = 0; j < M; j++) {
				newmap[i][j] = map[i][j];
			}
		}
		int arcidx = N;
		while (arcidx >= 0) {
			ArrayList<int[]> archer = new ArrayList<>();
			for (int i = 0; i < M; i++) {
				if (newmap[arcidx][i] == 2) {
					archer.add(new int[] { arcidx, i });
				}
			}
			ArrayList<int[]> enemy = new ArrayList<>();
			for (int i = 0; i < arcidx; i++) {
				for (int j = 0; j < M; j++) {
					if (newmap[i][j] == 1) {
						enemy.add(new int[] { i, j });
					}
				}
			}
			if (enemy.size() == 0)
				return;
			int enemylen = enemy.size();
			for (int i = 0; i < 3; i++) {
				int[] acrtmp = archer.get(i);
				int acrr = acrtmp[0];
				int acrc = acrtmp[1];
				PriorityQueue<int[]> canShoot = new PriorityQueue<>(new Comparator<int[]>() {
					@Override
					public int compare(int[] o1, int[] o2) {
						if (o1[0] == o2[0]) {
							return o1[2] - o2[2];
						}
						return o1[0] - o2[0];
					}
				});
				for (int j = 0; j < enemylen; j++) {
					int[] enmtmp = enemy.get(j);
					int enmr = enmtmp[0];
					int enmc = enmtmp[1];
					canShoot.offer(new int[] { Math.abs(acrr - enmr) + Math.abs(acrc - enmc), enmr, enmc });
				}
				int[] kill = canShoot.poll();
				if (kill[0] <= D) {
					int killr = kill[1];
					int killc = kill[2];
					if (newmap[killr][killc] == 1) {
						newmap[killr][killc] = 0;
						killcnt++;
					}
				}
			}
			arcidx--;
			for (int i = 0; i < M; i++) {
				newmap[arcidx][i] = newmap[arcidx + 1][i];
			}
			maxkill = Math.max(killcnt, maxkill);
		}
	}
}