giles
32aba1823d
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Test, Build, and Deploy / test-build-deploy (push) Failing after 29s
Run-length encoding via tail-recursive 4-arg accumulator:
let rle xs =
let rec aux xs cur n acc =
match xs with
| [] -> List.rev ((cur, n) :: acc)
| h :: t ->
if h = cur then aux t cur (n + 1) acc
else aux t h 1 ((cur, n) :: acc)
in
match xs with
| [] -> []
| h :: t -> aux t h 1 []
rle [1;1;1;2;2;3;3;3;3;1;1] = [(1,3);(2,2);(3,4);(1,2)]
sum of counts = 11 (matches input length)
The sum-of-counts test verifies that the encoding preserves total
length — drops or duplicates would diverge.
44 baseline programs total.
17 lines
341 B
OCaml
17 lines
341 B
OCaml
let rle xs =
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let rec aux xs cur n acc =
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match xs with
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| [] -> List.rev ((cur, n) :: acc)
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| h :: t ->
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if h = cur then aux t cur (n + 1) acc
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else aux t h 1 ((cur, n) :: acc)
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in
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match xs with
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| [] -> []
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| h :: t -> aux t h 1 []
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;;
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List.fold_left (fun acc (_, n) -> acc + n) 0
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(rle [1;1;1;2;2;3;3;3;3;1;1])
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