giles
3fe3b7b66f
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Test, Build, and Deploy / test-build-deploy (push) Failing after 23s
Siamese construction for odd-order magic squares: - place 1 at (0, n/2) - for k = 2..n^2, move up-right with (x-1+n) mod n wrap - if the target cell is taken, drop down one row instead for n=5, magic constant = n*(n^2+1)/2 = 5*26/2 = 65 Returns the main-diagonal sum (65 by construction). Tests 2D array via Array.init + Array.make, mod arithmetic with the (x-1+n) mod n idiom for negative-safe wrap, nested begin/end branches inside for-loop body. 166 baseline programs total.
28 lines
516 B
OCaml
28 lines
516 B
OCaml
let n = 5
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let make_magic () =
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let m = Array.init n (fun _ -> Array.make n 0) in
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let row = ref 0 in
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let col = ref (n / 2) in
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for k = 1 to n * n do
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m.(!row).(!col) <- k;
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let nr = (!row - 1 + n) mod n in
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let nc = (!col + 1) mod n in
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if m.(nr).(nc) <> 0 then begin
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row := (!row + 1) mod n
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end else begin
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row := nr;
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col := nc
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end
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done;
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m
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;;
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let m = make_magic () in
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let sum_diag = ref 0 in
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for i = 0 to n - 1 do
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sum_diag := !sum_diag + m.(i).(i)
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done;
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!sum_diag
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