giles
4761d41a0d
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Test, Build, and Deploy / test-build-deploy (push) Failing after 22s
Before: `:op` handler always evaluated both operands before dispatching
to ocaml-eval-op. For pure binops that's fine, but `&&` / `||` MUST
short-circuit:
if nr >= 0 && grid.(nr).(nc) = 0 then ...
When nr = -1, real OCaml never evaluates `grid.(-1)`. Our evaluator
did, and crashed with "nth: list/string and number".
Fix: special-case `&&` and `||` in :op dispatch, mirroring the same
pattern already used for `:=` and `<-`. Evaluate lhs, branch on it,
and only evaluate rhs when needed.
Latent since baseline 1 — earlier programs never triggered it because
the rhs was unconditionally safe.
bfs_grid.ml: shortest path through a 5x5 grid with walls. Standard
BFS using Queue.{push,pop,is_empty} + Array.init for the 2D distance
matrix. Path 0,0 -> ... -> 4,4 has length 8. 155 baseline programs
total.
43 lines
935 B
OCaml
43 lines
935 B
OCaml
let h = 5
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let w = 5
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let grid = [|
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[| 0; 0; 1; 0; 0 |];
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[| 1; 0; 1; 0; 1 |];
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[| 0; 0; 0; 0; 0 |];
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[| 0; 1; 1; 1; 0 |];
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[| 0; 0; 0; 0; 0 |]
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|]
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let step dist q r c nr nc =
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if nr >= 0 && nr < h && nc >= 0 && nc < w
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&& grid.(nr).(nc) = 0 && dist.(nr).(nc) = -1 then begin
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dist.(nr).(nc) <- dist.(r).(c) + 1;
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Queue.push (nr * 10 + nc) q
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end
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let bfs sr sc tr tc =
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let dist = Array.init h (fun _ -> Array.make w (-1)) in
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let q = Queue.create () in
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dist.(sr).(sc) <- 0;
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Queue.push (sr * 10 + sc) q;
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let go = ref true in
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while !go do
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if Queue.is_empty q then go := false
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else if dist.(tr).(tc) <> -1 then go := false
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else begin
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let rc = Queue.pop q in
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let r = rc / 10 in
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let c = rc mod 10 in
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step dist q r c (r - 1) c;
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step dist q r c (r + 1) c;
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step dist q r c r (c - 1);
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step dist q r c r (c + 1)
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end
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done;
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dist.(tr).(tc)
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;;
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bfs 0 0 4 4
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