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Test, Build, and Deploy / test-build-deploy (push) Failing after 26s
Each pass: 1. find_max in [0..size-1] 2. if max not at the right end, flip max to position 0 (if needed) 3. flip the size-prefix to push max to the end Inner 'flip k' reverses prefix [0..k] using two pointer refs lo/hi. Inner 'find_max k' walks 1..k tracking the max-position. pancake_sort [3;1;4;1;5;9;2;6] = 9 flips * 100 + a.(0) + a.(n-1) = 9 * 100 + 1 + 9 = 910 The output combines flip count and sorted endpoints, so the test verifies both that the sort terminates and that it sorts correctly. Tests two inner functions closing over the same Array, ref-based two-pointer flip, and downto loop with conditional flip dispatch. 77 baseline programs total.
34 lines
694 B
OCaml
34 lines
694 B
OCaml
let pancake_sort xs =
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let a = Array.of_list xs in
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let n = Array.length a in
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let flips = ref 0 in
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let flip k =
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let lo = ref 0 and hi = ref k in
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while !lo < !hi do
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let tmp = a.(!lo) in
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a.(!lo) <- a.(!hi);
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a.(!hi) <- tmp;
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lo := !lo + 1;
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hi := !hi - 1
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done;
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flips := !flips + 1
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in
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let find_max k =
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let m = ref 0 in
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for i = 1 to k do
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if a.(i) > a.(!m) then m := i
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done;
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!m
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in
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for size = n downto 2 do
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let mi = find_max (size - 1) in
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if mi <> size - 1 then begin
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if mi > 0 then flip mi;
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flip (size - 1)
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end
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done;
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!flips * 100 + a.(0) + a.(n - 1)
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;;
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pancake_sort [3; 1; 4; 1; 5; 9; 2; 6]
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