adventofcode/Day3_Part2.java at master · transidai1705/adventofcode · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
public class Day3_Part2 {

	private static final int INITIAL_SIZE = 5;

	public static void main(String[] args) {

		int numberToCheck = 312051;

		int size = INITIAL_SIZE;
		int currentSum = 0;

		int[][] map = new int[size][size];
		map[size/2][size/2] = 1;
		int currentX = 2;
		int currentY = 3;
		Direction direction = Direction.RIGHT;

		do
		{
			if (currentX == (size - 2) && currentY == (size - 1))
			{
				currentX++;
				currentY++;
				size += 2;
				map = populateDataToNewMap(size, map);
			}
			currentSum = getSumOfCurrentCell(map, currentX, currentY);
			map[currentX][currentY] = currentSum;
			switch (direction) {
			case LEFT:
				if (map[currentX + 1][currentY] == 0) {
					direction = Direction.DOWN;
					currentX = currentX + 1;
				} else {
					direction = Direction.LEFT;
					currentY = currentY - 1;
				}
				break;
			case RIGHT:
				if (map[currentX - 1][currentY] == 0) {
					direction = Direction.UP;
					currentX = currentX - 1;
				} else {
					direction = Direction.RIGHT;
					currentY = currentY + 1;
				}
				break;
			case UP:
				if (map[currentX][currentY - 1] == 0) {
					direction = Direction.LEFT;
					currentY = currentY - 1;
				} else {
					direction = Direction.UP;
					currentX = currentX - 1;
				}
				break;
			case DOWN:
				if (map[currentX][currentY + 1] == 0) {
					direction = Direction.RIGHT;
					currentY = currentY + 1;
				} else {
					direction = Direction.DOWN;
					currentX = currentX + 1;
				}
				break;
			default:
				break;
			}
		}
		while (currentSum < numberToCheck);

		System.out.println(currentSum);

	}

	private static int[][] populateDataToNewMap(int size, int[][] map) {
		int[][] newMap = new int[size][size];
		for (int i = 0; i < map.length; i++) {
			for (int j = 0; j < map.length; j++)
			{
				newMap[i + 1][j + 1] = map[i][j];
			}
		}
		return newMap;
	}

	private static int getSumOfCurrentCell(int[][] map, int currentY, int currentX)
	{
		return map[currentY + 1][currentX] + map[currentY - 1][currentX] + map[currentY][currentX + 1]
				+ map[currentY][currentX - 1] + map[currentY + 1][currentX + 1] + map[currentY + 1][currentX - 1]
				+ map[currentY - 1][currentX + 1] + map[currentY - 1][currentX - 1];
	}

	enum Direction	{
		LEFT, RIGHT, UP, DOWN;
	}


}