My yearly advent-of-code solutions
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
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 do l = 1, size(nodes(i)%x)
87 if(nodes(i)%x(j) == nodes(i)%x(l) .and. nodes(i)%y(j) == nodes(i)%y(l)) cycle ! don't compare same values
88 xdist = nodes(i)%x(j) - nodes(i)%x(l)
89 ydist = nodes(i)%y(j) - nodes(i)%y(l)
90 if(nodes(i)%x(j) + xdist > 0 .and. nodes(i)%x(j) + xdist <= 50 .and. &
91 nodes(i)%y(j) + ydist > 0 .and. nodes(i)%y(j) + ydist <= 50) then
92 if(.not. allocated(anti_x)) then
93 allocate(anti_x(1))
94 anti_x(1) = nodes(i)%x(j) + xdist
95 allocate(anti_y(1))
96 anti_y(1) = nodes(i)%y(j) + ydist
97 score = score + 1
98 else
99 found = .false.
100 do k = 1, size(anti_x)
101 if(anti_x(k) == nodes(i)%x(j) + xdist .and. anti_y(k) == nodes(i)%y(j) + ydist) then
102 found = .true.
103 exit
104 end if
105 end do
106 if(.not. found) then
107 call append_to_integer_array(anti_x, nodes(i)%x(j) + xdist)
108 call append_to_integer_array(anti_y, nodes(i)%y(j) + ydist)
109
110 score = score + 1
111 end if
112 end if
113 end if
114 if(nodes(i)%x(l) - xdist > 0 .and. nodes(i)%x(l) - xdist <= 50 .and. &
115 nodes(i)%y(l) - ydist > 0 .and. nodes(i)%y(l) - ydist <= 50) then
116 if(.not. allocated(anti_x)) then
117 allocate(anti_x(1))
118 anti_x(1) = nodes(i)%x(l) - xdist
119 allocate(anti_y(1))
120 anti_y(1) = nodes(i)%y(l) - ydist
121 score = score + 1
122 else
123 found = .false.
124 do k = 1, size(anti_x)
125 if(anti_x(k) == nodes(i)%x(l) - xdist .and. anti_y(k) == nodes(i)%y(l) - ydist) then
126 found = .true.
127 exit
128 end if
129 end do
130 if(.not. found) then
131 call append_to_integer_array(anti_x, nodes(i)%x(l) - xdist)
132 call append_to_integer_array(anti_y, nodes(i)%y(l) - ydist)
133
134 score = score + 1
135 end if
136 end if
137 end if
138 end do
139 end do
140 end do
141 print*, "Total : ", score
142end program day_08