giles
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Test, Build, and Deploy / test-build-deploy (push) Failing after 22s
Count 4-connected components of 1-cells via DFS flood from every
unvisited 1-cell.
Grid (1s shown as #):
# # . . . # #
# . . . # # .
. . # # . . .
. # # # . # #
# . . . . # .
# # . # # # .
Components:
{(0,0),(0,1),(1,0)}
{(0,5),(0,6),(1,4),(1,5)}
{(2,2),(2,3),(3,1),(3,2),(3,3)}
{(3,5),(3,6),(4,5),(5,3),(5,4),(5,5)}
{(4,0),(5,0),(5,1)}
-> 5 islands
Complementary to flood_fill.ml (largest component); this counts
total components.
Tests recursive function returning () at early-exit branches,
ordered double-for entry pass triggering one fill per island root.
180 baseline programs total.
38 lines
829 B
OCaml
38 lines
829 B
OCaml
let h = 6
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let w = 7
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let grid = [|
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[| 1; 1; 0; 0; 0; 1; 1 |];
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[| 1; 0; 0; 0; 1; 1; 0 |];
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[| 0; 0; 1; 1; 0; 0; 0 |];
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[| 0; 1; 1; 1; 0; 1; 1 |];
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[| 1; 0; 0; 0; 0; 1; 0 |];
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[| 1; 1; 0; 1; 1; 1; 0 |]
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|]
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let rec fill visited r c =
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if r < 0 || r >= h || c < 0 || c >= w then ()
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else if visited.(r).(c) || grid.(r).(c) = 0 then ()
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else begin
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visited.(r).(c) <- true;
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fill visited (r - 1) c;
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fill visited (r + 1) c;
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fill visited r (c - 1);
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fill visited r (c + 1)
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end
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let count_islands () =
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let visited = Array.init h (fun _ -> Array.make w false) in
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let count = ref 0 in
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for r = 0 to h - 1 do
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for c = 0 to w - 1 do
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if grid.(r).(c) = 1 && not visited.(r).(c) then begin
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count := !count + 1;
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fill visited r c
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end
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done
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done;
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!count
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;;
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count_islands ()
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