How To Solve Domino Puzzles
The Domino puzzle is based on the well-known game played with rectangular tiles.
The puzzle consists of a rectangular grid, each cell occupied by a single-digit number. The grid represents a set of domino pieces in a rectangular array.
Each domino piece is a rectangle containing two ends. Each end has a number. Depending on the size of the grid (and, therefore, the puzzle's difficulty), each end can contain a number from 0 to 9. The puzzle will specify the number range for that puzzle. Smaller puzzles may include numbers from 0 to 3.
There are no duplicate dominos in any puzzle. All the dominos in the array are contained in the puzzle. For example, if the puzzle uses dominos from 0-0 to 3-3, you can expect to find all the following ten pieces in the puzzle:
0-0, 0-1, 0-2, 0-3, 1-1, 1-2, 1-3, 2-2, 2-3, 3-3.
Note that a piece may be flipped, so the 0-1 and 1-0 are the same single piece.
To solve the puzzle, outline (draw a border around) pairs of adjacent numbers so that every piece of the domino set is revealed. The pieces can be laid out vertically or horizontally. No number can be a part of two pieces - so there is no overlapping.
