The Battleships Puzzle is a five-by-five solitaire logic puzzle in which you place a disclosed three-ship fleet so that every printed row and column clue matches, all ships run straight, and no ship touches another ship even diagonally, scoring 940 points from the six Space actions that complete the board. Unlike the two-player guessing game where opponents call shots at hidden ships, every decision in Battleships Puzzle happens on a single visible grid: the fleet must be located, not attacked. The fixture shipped with the game includes one cruiser of length 3, one destroyer of length 2, and one submarine of length 1, for six occupied cells in total. Conceptis publishes the canonical solitaire Battleships rule set, and the same straight-ship, no-touch, fleet, and line-count constraints appear independently in Games Magazine's print instructions, so the logic matches a long-standing standard rather than a one-off design.
What the Battleships Puzzle Is
Battleships Puzzle is a single-player logic puzzle, sometimes called Solitaire Battleships or Battleship Solitaire, where the goal is to find the location of a small fleet using only the printed line totals. The player works with a fixed five-by-five grid, a known fleet shape, and a row and column clue printed beside every line. Each clue tells exactly how many ship segments fall in that line. The puzzle is solved when the placed fleet matches every row clue, every column clue, the declared fleet shape, the no-touch rule, and the straight-ship rule all at the same time.
The key contrast with the classic paper-and-pen Battleships game is that there is no opponent guessing. Both the clues and the validation are visible on the same screen, so each ship placement either advances the solution or produces a contradiction. Because the clues are tightly constrained, a small 5x5 board with a six-cell fleet keeps the search space tight enough that the included fixture can be checked by hand in a few minutes.
Board Layout, Fleet, and Clues
The fixture shipped with Battleships Puzzle is a five-by-five grid of square cells surrounded by ten clues. Reading from top to bottom, the row clues are 3, 0, 1, 1, and 1. Reading from left to right, the column clues are 1, 2, 1, 0, and 2. The fleet declared for the board is exactly one ship of length 3, one ship of length 2, and one ship of length 1. Six cells end up occupied and nineteen cells remain water. Because the row totals and column totals must agree with the same six cells, the line clues are tightly coupled: satisfying one side without the other is impossible.
| Line | Clue (top to bottom / left to right) | Occupied cells on the solved board |
|---|---|---|
| Row 1 | 3 | (0,0), (0,1), (0,2) |
| Row 2 | 0 | none |
| Row 3 | 1 | (2,4) |
| Row 4 | 1 | (3,4) |
| Row 5 | 1 | (4,1) |
| Column 1 | 1 | (0,0) |
| Column 2 | 2 | (0,1), (4,1) |
| Column 3 | 1 | (0,2) |
| Column 4 | 0 | none |
| Column 5 | 2 | (2,4), (3,4) |
The row of zeros is a powerful starting clue. Any line whose clue is zero must be entirely water, which means every neighbor of that line, including diagonally adjacent cells, cannot contain a ship segment because of the no-touch rule. Row 2 is therefore a guard rail that forces both row 2's diagonals and the lower portion of the grid to be cleared before any ship lands there. That single observation removes a large part of the search space before any ship is placed.
The No-Touch and Straight-Ship Rules
Two rule pairs govern how a ship can be drawn on the grid. First, every ship must be a straight line. Each ship is either horizontal or vertical, runs the entire length declared by the fleet, and cannot bend around a corner. A connected group that spans more than one row and more than one column is treated by the validator as a bent ship and the board records a contradiction. Second, distinct ships must be separated by at least one cell of water in every direction. Ships may not share an edge, and they also may not touch at a corner, so the cells surrounding every ship must stay empty.
These two rules together create a useful tightening effect. As soon as the length-3 ship is fixed, every cell touching any of its three segments, including all eight diagonal neighbors, is forced to be water, which in turn forces the next ship into a narrower corridor. Conceptis documents the same separation rule, and the included validator mirrors it directly by scanning diagonal neighbors across different connected components and rejecting any pair that meets at a corner.
How to Play Battleships Puzzle Step by Step
The fastest way to get a complete board on the included fixture is to use the printed line clues as a constraint solver and place ships one by one. The following order reflects how the disclosed solution falls into place using only the clues, the fleet shape, and the no-touch rule.
- Read every clue before placing anything. Note row 2 is 0, column 4 is 0, column 2 totals 2, and row 1 totals 3. These four facts narrow the search to a handful of cells.
- Reserve row 2 and column 4 as water. Mark them, and remember that all of their immediate diagonal neighbors must also stay empty because of the separation rule.
- Place the length-3 ship on the only line that can hold three. Row 1 has clue 3 and is the only row with room for a three-segment horizontal ship. Drop a length-3 ship across cells (0,0), (0,1), and (0,2).
- Use the column clues to fix column 5. Column 5 has clue 2 and column 2 has clue 2. The cells (2,4) and (3,4) are both safe from row 2 and from the top row ship, so the length-2 ship drops vertically into column 5 at (2,4) and (3,4).
- Place the length-1 submarine from the remaining clue. Column 2 still needs one more ship segment, and row 5 still needs one. The single empty cell that satisfies both is (4,1). Drop the submarine there.
- Verify all ten clues and the separation rule. Each row and column should now show its printed total, no ship should touch another, and every ship should be straight. Press Enter on unused cells to mark water if it helps your reasoning.
This is the disclosed solution: the length-3 ship across the top row, the length-2 ship straight down the last column, and the submarine isolated in row 5, column 2. Six Space actions from a clean board complete it, and the score drops from 1,000 to 940.
Controls, Water Marks, and Scoring
The keyboard controls cover every interaction on the grid. The arrow keys move the active cell around the board, Space adds or removes a ship segment on the highlighted cell, and Enter places or removes an optional water mark on a cell that is not yet a ship. Mouse and touch users can click to toggle a ship segment and use the context-menu gesture to mark water. Restart clears ships, water marks, score, moves, and contradiction state, and a completed best score may be stored in localStorage for later comparison.
Water marks are reasoning aids only. They never count toward the fleet, never affect validation, and never change the score, so a player can mark the empty cells of row 2 and column 4 freely without affecting the result. Ship actions, on the other hand, drive the score directly: the validator recomputes connected components after every Space press, the score is computed as the maximum of 0 and 1,000 minus 10 times the number of ship actions, and the fixture's perfect finish lands on 940 after six clean actions. Press Escape twice in quick succession to swap the board for a shared simulated spreadsheet cover, then press Escape twice again to return to the unchanged fleet.
Strategy Notes for Repeated Play
On a fresh play, the zero clues are always the first stop. Any line whose clue is 0 becomes water, and any cell diagonal to that line also becomes water because of the separation rule. The largest line clue usually reveals where the longest ship belongs, because only one line can hold a ship of that length without exceeding its total. Conceptis publishes the rule reference and Games Magazine independently describes the same straight-ship, no-touch, fleet, and line-count constraints, so the steps above stay anchored to those published rules.
When a placement is rejected, read the reason carefully. A bent ship rejection means the connected group spans more than one row and more than one column, so an orthogonal neighbor was incorrectly merged into a different ship. A diagonal-contact rejection means two segments from different components meet at a corner. A line-overflow rejection means too many ship segments already sit in that line, while a fleet-size rejection means more than six segments are on the board. Each error pinpoints a different mistake, and correcting one placement usually resolves the rest of the contradictions in the same pass.
For comparison, the same fleet-and-clues pattern appears in related solitaire logic puzzles where small line totals and adjacency rules force a unique answer under similar constraints. Practising those puzzles alongside Battleships Puzzle sharpens the same core skill of using exact printed totals to eliminate cells and place a multi-piece shape on a compact grid.
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