My yearly advent-of-code solutions
treybastian.com
1module day_08_utils
2 implicit none
3 type node
4 character :: c
5 integer, allocatable :: x(:), y(:)
6 end type node
7contains
8 subroutine append_to_integer_array(arr, val)
9 implicit none
10 integer, allocatable, intent(inout) :: arr(:)
11 integer, intent(in) :: val
12 integer, allocatable :: temp(:)
13 if(.not. allocated(arr)) then
14 ERROR STOP 'Array not allocated'
15 end if
16 allocate(temp(size(arr) + 1))
17 temp(1:size(arr)) = arr
18 temp(size(arr) + 1) = val
19 call move_alloc(temp, arr)
20 end subroutine append_to_integer_array
21
22 subroutine add_node(nodes, c, x, y)
23 type(node), allocatable, intent(inout) :: nodes(:)
24 type(node), allocatable :: temp(:)
25 character, intent(in) :: c
26 integer, intent(in) :: x, y
27 integer :: i
28 do i = 1, size(nodes)
29 if (nodes(i)%c == c) then
30 if(.not. allocated(nodes(i)%x)) then
31 allocate(nodes(i)%x(1))
32 nodes(i)%x(1) = x
33 else
34 call append_to_integer_array(nodes(i)%x, x)
35 end if
36 if(.not. allocated(nodes(i)%y)) then
37 allocate(nodes(i)%y(1))
38 nodes(i)%y(1) = y
39 else
40 call append_to_integer_array(nodes(i)%y, y)
41 end if
42 return
43 end if
44 end do
45 allocate(temp(size(nodes) + 1))
46 temp(1:size(nodes)) = nodes
47 allocate(temp(size(nodes) + 1)%x(1))
48 allocate(temp(size(nodes) + 1)%y(1))
49 temp(size(nodes) + 1)%c = c
50 temp(size(nodes) + 1)%x(1) = x
51 temp(size(nodes) + 1)%y(1) = y
52 call move_alloc(temp, nodes)
53 end subroutine add_node
54end module day_08_utils
55
56program day_08
57 use day_08_utils
58 implicit none
59 character(len=50) :: lines(50)
60 integer :: io, i, j, k, l, score, xdist, ydist, next_x, next_y
61 integer, allocatable :: anti_x(:), anti_y(:)
62 type(node), allocatable :: nodes(:)
63 logical :: found
64
65 open(newunit=io, file='day_08_input.txt', status='old', action='read')
66 read(io, '(A)') lines
67 score = 0
68 do i = 1, 50
69 do j = 1, 50
70 if(lines(i)(j:j) /= '.') then
71 if(.not. allocated(nodes)) then
72 allocate(nodes(1))
73 nodes(1)%c = lines(i)(j:j)
74 allocate(nodes(1)%x(1))
75 allocate(nodes(1)%y(1))
76 nodes(1)%x(1) = j
77 nodes(1)%y(1) = i
78 else
79 call add_node(nodes, lines(i)(j:j), j, i)
80 end if
81 end if
82 end do
83 end do
84 do i = 1, size(nodes)
85 do j = 1, size(nodes(i)%x)
86 if(.not. allocated(anti_x)) then
87 allocate(anti_x(1))
88 anti_x(1) = nodes(i)%x(j)
89 allocate(anti_y(1))
90 anti_y(1) = nodes(i)%y(j)
91 score = score + 1
92 else
93 found = .false.
94 do k = 1, size(anti_x)
95 if(anti_x(k) == nodes(i)%x(j) .and. anti_y(k) == nodes(i)%y(j)) then
96 found = .true.
97 exit
98 end if
99 end do
100 if(.not. found) then
101 call append_to_integer_array(anti_x, nodes(i)%x(j))
102 call append_to_integer_array(anti_y, nodes(i)%y(j))
103
104 score = score + 1
105 end if
106 end if
107 do l = 1, size(nodes(i)%x)
108 if(nodes(i)%x(j) == nodes(i)%x(l) .and. nodes(i)%y(j) == nodes(i)%y(l)) cycle ! don't compare same values
109 xdist = nodes(i)%x(j) - nodes(i)%x(l)
110 ydist = nodes(i)%y(j) - nodes(i)%y(l)
111 next_x = nodes(i)%x(j) + xdist
112 next_y = nodes(i)%y(j) + ydist
113 do
114 if(next_x> 0 .and. next_x <= 50 .and. &
115 next_y > 0 .and. next_y <= 50) then
116 found = .false.
117 do k = 1, size(anti_x)
118 if(anti_x(k) == next_x .and. anti_y(k) == next_y) then
119 found = .true.
120 exit
121 end if
122 end do
123 if(.not. found) then
124 call append_to_integer_array(anti_x, next_x)
125 call append_to_integer_array(anti_y, next_y)
126
127 score = score + 1
128 end if
129 next_x = next_x + xdist
130 next_y = next_y + ydist
131 else
132 exit
133 end if
134 end do
135 next_x = nodes(i)%x(l) - xdist
136 next_y = nodes(i)%y(l) - ydist
137 do
138 if(next_x > 0 .and. next_x <= 50 .and. &
139 next_y > 0 .and. next_y <= 50) then
140 found = .false.
141 do k = 1, size(anti_x)
142 if(anti_x(k) == next_x .and. anti_y(k) == next_y) then
143 found = .true.
144 exit
145 end if
146 end do
147 if(.not. found) then
148 call append_to_integer_array(anti_x, next_x)
149 call append_to_integer_array(anti_y, next_y)
150
151 score = score + 1
152 end if
153 next_x = next_x - xdist
154 next_y = next_y - ydist
155
156 else
157 exit
158 end if
159 end do
160 end do
161 end do
162 end do
163 print*, "Total : ", score
164end program day_08