49 lines
1.4 KiB
OCaml
49 lines
1.4 KiB
OCaml
let start = 109165;;
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let finish = 576723;;
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let range start finish =
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let rec generator curr fin acc =
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if (curr=fin) then List.rev(fin::acc)
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else generator (curr+1) fin (curr::acc)
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in generator start finish [];;
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let domain = range 109165 576723;;
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let digits2list number =
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let rec aux acc x =
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if x <= 0 then acc
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else aux ((x mod 10)::acc) (x/10)
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in aux [] number;;
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let isNotDecreasing number =
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let list = digits2list number
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in fst (List.fold_left (fun (b,p) n -> if n<p then (false,n) else (b,n)) (true, (List.hd list)) (List.tl list));;
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let hasAnyPair number =
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let list = digits2list number
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in fst (List.fold_left (fun (b,p) n -> if p=n then (true,n) else (b,n)) (false, (List.hd list)) (List.tl list));;
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let predicate number = isNotDecreasing number && hasAnyPair number;;
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let filtered = List.filter (fun x -> predicate x) domain;;
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let result1 = List.length filtered;; (* part 1 result *)
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(* ====================== PART 2 ====================== *)
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let predicatePart2 number =
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let list = List.rev(-1::digits2list number)
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in let (_,_,comboList) = List.fold_left (fun (prev, count, acc) next ->
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if prev=next then (next, count+1, acc)
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else (next, 1, count::acc)
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) ((List.hd list), 1, []) (List.tl list)
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in List.mem 2 comboList;;
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let lol = predicatePart2 11010343;;
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let filtered2 = List.filter (fun x -> predicatePart2 x) filtered;;
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let result2 = List.length filtered2;;
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