application/octet-stream
•
1.91 KB
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60 lines
#!/usr/bin/env nujel
[defun char-to-score [cc]
[case cc
[[#\)] 3]
[[#\]] 57]
[[#\}] 1197]
[[#\>] 25137]
[otherwise 0]
]
]
[defun p2-score [cc]
[case cc
[[#\)] 1]
[[#\]] 2]
[[#\}] 3]
[[#\>] 4]
[otherwise 0]
]
]
[defun calc-part2-score [stack α]
[if stack
[calc-part2-score [cdr stack]
[+ [* 5 α]
[p2-score [car stack]]]]
α]
]
[defun find-first-syntax-error [line]
[def stack #nil]
[try [\ [ε] [if [== [car ε] :return]
[cons :part1 [char-to-score [cadr ε]]]
[throw ε]]]
[for [i 0 [string/length line]]
[def cc [char-at line i]]
[case cc
[[#\(] [set! stack [cons #\) stack]]]
[[#\{] [set! stack [cons #\} stack]]]
[[#\[] [set! stack [cons #\] stack]]]
[[#\<] [set! stack [cons #\> stack]]]
[[#\) #\} #\] #\>] [if [== cc [car stack]]
[set! stack [cdr stack]]
[throw [list :return cc i]]]]
]
]
[calc-part2-score stack 0]
]
]
[def lines [split [file/read "day10.input"] "\n"]]
[def res [map find-first-syntax-error lines]]
[def p1-res [reduce [\ [α β] [if [== :part1 [car β]] [+ α [cdr β]] α]] res 0]]
[def incomplete-lines [list/sort [filter [\ [α] [!= :part1 [car α]]] res]]]
[def p2-res [list/ref incomplete-lines [/ [length incomplete-lines] 2]]]
[when [!= p1-res 315693]
[throw [list :wrong-result "Wrong result" p1-res]]]
[when [!= p2-res 1870887234]
[throw [list :wrong-result "Wrong result" p2-res]]]
