A Dominosa puzzle (also known as Solitaire Dominoes and Domino Hunt) is a type of logic puzzle where the aim is to complete a grid following deceptively simple rules.
Free Printable Dominosa Puzzles HERE!
The grid is filled with dominoes – a domino is a pair of numbers, starting a 0-0 and with the highest number dependin on the grid size. A grid size 5 x 4 contains 20 numbers which means there are 10 domino tiles, from 0-0 to 3-3. with a 11 x 10 grid containing 110 numbers which means there are 55 domino tiles, from 0-0 to 9-9.
Here is an example of a Dominosa puzzle in a 7×6 grid (42 cells = 21 dominoes:
And this is what the solution to the puzzle above looks like:
Not how there is one of each ‘domino’ or pair of numbers in this dominosa puzzle solution.
How to Solve Domino Puzzles (Dominosa)
When solving Domino puzzles, also known as Dominosa, there are several strategies you can employ to crack the puzzle successfully.
Tip: Write down a list of possible numbers and tick them off as you go!
1: Identifying Single Placement Options:
- Look for dominoes that can only fit in one specific spot within the grid. In the example above, you will see there is only one possible placement for 0,0.
- Once identified, mark that domino as placed, draw a border around it, and cross it off from the list of possible placements.
As you can see in the example below, the dominoes we have marked can only be placed in these positions. For example, there is only one set of adjacent 0s.
Utilizing Cell Value Constraints:
- Recognize that each cell in the puzzle belongs to a domino with a specific value.
- Pay attention to corners and edges, where the values are limited due to adjacent cells.
- If, for example, a corner cell contains ‘1’ and its neighboring cells contain ‘2’, you can deduce that a ‘1-2’ domino must be in that corner.
Process of Elimination
- Remember to keep eliminating any moves which are against the rules. For example, don’t place a domino where it leaves an odd number.
For example, we can see in the dominosa grid below that there are three options for placing the domino 1,3 (marked in blue). However, if we were to mark the domino in the second option, it would leave us with a single number ‘1’ (circled) which means the grid cannot be completed. Therefore we can eliminate this as a possible placement.
Narrow Down Your Options:
- Keep checking the dominosa grid to see what affect you are having as you mark your solutions. This will narrow down your options.
- If necessary, pencil in solutions to help reduce possible placements.
As we can see in the example below, as we have marked more dominoes, so there are less options available. We know that the cells marked in blue have to be correct placements, because if we were to mark the dominoes in any other way, we would be left with single odd numbers and the grid cannot be completed.
By using these strategies effectively, you can solve most Domino puzzles with logical reasoning. Remember, each puzzle has a unique solution that can be attained through pure logic.