giles
4fdf6980da
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Test, Build, and Deploy / test-build-deploy (push) Failing after 23s
Previously `a.(i) <- if c then x else y` failed with "unexpected token keyword if" because parse-binop-rhs called parse-prefix for the rhs, which doesn't accept if/match/let/fun. Real OCaml allows full expressions on the rhs of <-/:=. Fix: special-case prec-1 ops in parse-binop-rhs to call parse-expr-no-seq instead of parse-prefix. The recursive parse-binop-rhs with min-prec restored after picks up any further chained <- (since both ops are right-associative with no higher-prec binops above them). Manacher baseline updated to use bare `if` on rhs of <-, removing the parens workaround from iter 235. 607/607 regressions remain clean.
33 lines
759 B
OCaml
33 lines
759 B
OCaml
let manacher s =
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let n = String.length s in
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let m = 2 * n + 1 in
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let t = Array.make m '#' in
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for i = 0 to n - 1 do
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t.(2 * i + 1) <- s.[i]
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done;
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let p = Array.make m 0 in
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let center = ref 0 and right = ref 0 in
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let max_p = ref 0 in
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for i = 0 to m - 1 do
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let mirror = 2 * !center - i in
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if i < !right then begin
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let v = !right - i in
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let pm = p.(mirror) in
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p.(i) <- if pm < v then pm else v
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end;
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while i + p.(i) + 1 < m && i - p.(i) - 1 >= 0
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&& t.(i + p.(i) + 1) = t.(i - p.(i) - 1) do
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p.(i) <- p.(i) + 1
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done;
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if i + p.(i) > !right then begin
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center := i;
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right := i + p.(i)
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end;
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if p.(i) > !max_p then max_p := p.(i)
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done;
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!max_p
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;;
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manacher "babadaba"
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