231128 기둥과 보 설치

private boolean[][] pillar;
private boolean[][] bar;

public int[][] solution(int n, int[][] buildFrame) {
	pillar = new boolean[n + 1][n + 1];
	bar = new boolean[n + 1][n + 1];

	int count = 0;
	for (int[] build : buildFrame) {
		int x = build[0];
		int y = build[1];
		int type = build[2];
		int action = build[3];

		switch (type) {
			case 0:
				count = processPillar(n, count, x, y, action);
				break;

			case 1:
				count = processBar(n, count, x, y, action);
				break;

			default:
				break;
		}
	}

	return getResultArray(count);
}

private int processBar(int n, int count, int x, int y, int action) {
	if (action == 1) {
		if (checkBar(x, y)) {
			bar[x][y] = true;
			count++;
		}
	} else {
		bar[x][y] = false;
		if (!canDelete(n))
			bar[x][y] = true;
		else
			count--;
	}
	return count;
}

private int processPillar(int n, int count, int x, int y, int action) {
	if (action == 1) {
		if (checkPillar(x, y)) {
			pillar[x][y] = true;
			count++;
		}
	} else {
		pillar[x][y] = false;
		if (!canDelete(n))
			pillar[x][y] = true;
		else
			count--;
	}
	return count;
}

private int[][] getResultArray(int count) {
	int[][] result = new int[count][3];
	int idx = 0;

	for (int i = 0; i < pillar.length; i++) {
		for (int j = 0; j < pillar[i].length; j++) {
			if (pillar[i][j]) {
				result[idx][0] = i;
				result[idx][1] = j;
				result[idx++][2] = 0;
			}
			if (bar[i][j]) {
				result[idx][0] = i;
				result[idx][1] = j;
				result[idx++][2] = 1;
			}
		}
	}

	return result;
}

private boolean canDelete(int n) {
	for (int i = 0; i <= n; i++) {
		for (int j = 0; j <= n; j++) {
			if (pillar[i][j] && !checkPillar(i, j))
				return false;
			if (bar[i][j] && !checkBar(i, j))
				return false;
		}
	}
	return true;
}

private boolean checkPillar(int x, int y) {
	return (y == 0) || (y > 0 && pillar[x][y - 1]) || (x > 0 && bar[x - 1][y] || bar[x][y]);
}

private boolean checkBar(int x, int y) {
	return (y > 0 && pillar[x][y - 1] || pillar[x + 1][y - 1]) || (x > 0 && bar[x - 1][y] && bar[x + 1][y]);
}

출처:https://school.programmers.co.kr/learn/courses/30/lessons/60061