application/octet-stream
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2.70 KB
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74 lines
#!/usr/bin/env nujel
[defn map/set/row [data y line w]
[def cols [map [split line ""] int]]
[dotimes [x w]
[array/2d/set! data x y [car cols]]
[cdr! cols]]]
[defn map/load [filename w h]
[def ret [array/2d/allocate w h]]
[def lines [split [file/read filename] "\n"]]
[dotimes [y h]
[map/set/row ret y [car lines] w]
[cdr! lines]]
ret]
[defn map/supersize [in]
[def out [array/2d/allocate [* 5 [in :width]] [* 5 [in :height]]]]
[dotimes [x [in :width]]
[dotimes [y [in :height]]
[dotimes [cx 5]
[dotimes [cy 5]
[array/2d/set! out
[+ x [* cx [in :width]]]
[+ y [* cy [in :height]]]
[+ 1 [rem [+ -1 cx cy [array/2d/ref in x y]] 9]]]
[array/2d/set! out
[+ x [* cx [in :width]]]
[+ y [* cy [in :height]]]
[+ 1 [rem [+ -1 cx cy [array/2d/ref in x y]] 9]]]
]]
]]
out
]
[defn queue/insert-sorted [q items]
[if [and q [< [caar q] [caar items]]]
[cons [car q] [queue/insert-sorted [cdr q] items]]
[if items
[cons [car items] [queue/insert-sorted q [cdr items]]]
q]]]
[defn map/walk [cmap]
[def total-risk [array/2d/allocate [cmap :width] [cmap :height]]]
[array/fill! [total-risk :data] 9999999999]
[def x-max [- [cmap :width] 1]]
[def y-max [- [cmap :height] 1]]
[def q [list [list 0 x-max y-max]]]
[while q
[def cur [car q]]
[cdr! q]
[def risk [car cur]]
[def x [cadr cur]]
[def y [caddr cur]]
[def crisk [array/2d/ref total-risk x y]]
[when [< risk crisk]
[array/2d/set! total-risk x y risk]
[+= risk [array/2d/ref cmap x y]]
[def tmp #nil]
[when [< x x-max] [set! tmp [cons [list risk [+ x 1] y] tmp]]]
[when [< y y-max] [set! tmp [cons [list risk x [+ y 1]] tmp]]]
[when [> y 0] [set! tmp [cons [list risk x [- y 1]] tmp]]]
[when [> x 0] [set! tmp [cons [list risk [- x 1] y] tmp]]]
[when tmp [set! q [queue/insert-sorted q tmp]]]
]]
[array/2d/ref total-risk 0 0]]
[def res-p1 [map/walk [map/load "day15.input" 100 100]]]
[when [!= res-p1 315]
[throw [list :wrong-result "Wrong result" res-p1]]]
[def res-p2 [map/walk [map/supersize [map/load "day15.input" 100 100]]]]
[when [!= res-p2 3040]
[throw [list :wrong-result "Wrong result" res-p2]]]
