advent/day8.rb at main · flanderb/advent · 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
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
class Forest
    def initialize(input)
        @forest = input_file(input)
        @viewable_trees = find_viewable_trees(@forest)
    end

    attr_reader :viewable_trees

    def input_file(input)
        forest = Array.new
        i = 0
        File.foreach(input) do |row|
            row = row.gsub("\n", "")
            forest.push(row.split(//).map{|char| char.to_i})
            i += 1
        end
        return forest
    end

    def find_viewable_trees(forest)
        viewable_trees = Array.new
        # x, y = 0, 0

        forest.each_index do |row|
            forest[row].each_index do |column|
                puts "[#{row}, #{column}] = #{forest[row][column]}"
                viewable = viewable_tree(forest, row, column)
                # puts viewable
                if viewable
                    viewable_trees.push("#{row}#{column}")
                end
            end
        end
        return viewable_trees
    end

    def viewable_tree(forest, row, column)
        east = viewable_from_east?(forest, row, column)
        west = viewable_from_west?(forest, row, column)
        north = viewable_from_north?(forest, row, column)
        south = viewable_from_south?(forest, row, column)

        p "[#{row},#{column}}] north = #{north}"
        p "[#{row},#{column}}] south = #{south}"
        p "[#{row},#{column}}] east = #{east}"
        p "[#{row},#{column}}] west = #{west}"
        p "#{east || west || north || south}"


        return east || west || north || south
    end


    def viewable_from_east?(forest, row, column)
        #get height of tree
        height = forest[row][column]
        height_to_east = -1
        p "[#{row}][#{column}] east -_---_-_-_-_-_-_-_"
        for a in 0..column-1
            p "forest[#{row}][#{a}] = #{forest[row][a]}"
            if forest[row][a] > height_to_east #&& column != a
                height_to_east = forest[row][a]
            end
        end
        # p "forest[#{x}][#{y}]"
        p height
        p height_to_east
        p height > height_to_east
        return height > height_to_east
    end

    def viewable_from_west?(forest, row, column)
        #get height of tree
        height = forest[row][column]
        height_to_west = -1
        p "[#{row}][#{column}] west -_---_-_-_-_-_-_-_"
        for a in column+1..forest[0].length-1
            p "forest[#{row}][#{a}] = #{forest[row][a]}"
            if forest[row][a] > height_to_west #&& a != forest[0].length
                height_to_west = forest[row][a]
            end
        end
        # p "forest[#{x}][#{y}]"
        p height
        p height_to_west
        p height > height_to_west
        return height > height_to_west
    end

    def viewable_from_north?(forest, row, column)
        #get height of tree
        height = forest[row][column]
        height_to_north = -1
        p "[#{row}][#{column}] north -_---_-_-_-_-_-_-_"
        for a in 0..row-1
            p "forest[#{a}][#{column}] = #{forest[a][column]}"
            if forest[a][column] > height_to_north #&& a != forest.length
                height_to_north = forest[a][column]
            end
        end
        # p "forest[#{x}][#{y}]"
        p height
        p height_to_north
        p height > height_to_north
        return height > height_to_north
    end
end

def viewable_from_south?(forest, row, column)
    #get height of tree
    height = forest[row][column]
    height_to_south = -1
    p "[#{row}][#{column}] south -_---_-_-_-_-_-_-_"
    for a in row+1..forest.length-1
        p "forest[#{a}][#{column}] = #{forest[a][column]}"
        if forest[a][column] > height_to_south #&& a != forest.length
            height_to_south = forest[a][column]
        end
    end
    # p "forest[#{x}][#{y}]"
    p height
    p height_to_south
    p height > height_to_south
    return height > height_to_south
end


today = Forest.new("day8i.txt")
p today.viewable_trees
p today.viewable_trees.length