Guns and Butter

Divide the grid into guns and butter as follows:

  • All battleships (guns) and dominoes (sticks of butter) must be used exactly once.
  • No two battleships may touch each other, not even diagonally.
  • No battleship may be placed on a ~ symbol, which signifies blank/water.
  • Numbers outside the grid indicate how many battleship segments are in that row/column.

Here is an example puzzle and its solution. The example uses a double-4 set of dominoes and a reduced set of ships; the puzzle itself uses a double-8 set and a standard set of ships.

~~
~1
~2
~3
~4
11
12
13
14
22
23
24
33
34
44


The puzzle below is interactive and supports undo/redo.

  • Click or Shift-click a cell to cycle through unknown, guns, and butter. You can also use the Space key for this.
  • Click the edge of a cell to place a domino between the two cells. You can also use Shift+arrow keys to do this.
  • You cannot place a domino in a place where it would be invalid (e.g. because a battleship is in the way).
  • You can click on the dominoes/ships below the puzzle to mark them as used.
  • You can undo with Ctrl+Z and redo with Ctrl+Y.
~~
~1
~2
~3
~4
~5
~6
~7
~8
11
12
13
14
15
16
17
18
22
23
24
25
26
27
28
33
34
35
36
37
38
44
45
46
47
48
55
56
57
58
66
67
68
77
78
88
~~~1~2~3
~4~5~6~7
~8111213
14151617
18222324
25262728
33343536
37384445
46474855
56575866
67687778
88

When the grid is complete, extract an answer by looking around the four 1x1 ships.