Kakuro Game: Cross Sums

Also known as Cross Sums, Kakuro is a mix between a crossword and sudoku puzzle. Unlike a crossword puzzle where the clue is a word or phrase, a Kakuro clue is a number that the corresponding answer cells must add up to. That’s where the sudoku part comes in. Each clue has at least 2 and no more than 9 answer cells. Each answer cell must be a single digit (1-9). Duplicate digits are not allowed within a clue (4 = 1+3, 4 ≠ 2+2).

How to Play:

Kakuro is a crossword-like puzzle game that uses numbers for both the clues and answers.

The Basics

• The value for a cell must be 1-9
• The answer cells must add up to the clue
• Duplicate numbers are not allowed within a clue (4=1+3, 4≠2+2)
• Each puzzle has a unique solution that can be solved without guesswork

Puzzle Layout

1. The number 11 is a clue
2. These 2 answer cells need to add up to 11
3. Possible combinations for the horizontal (11) and vertical (3) clues

Solving a Simple Puzzle

Let’s solve a simple 3×3 puzzle step by step. Keep in mind that there are many different ways to arrive at the same unique solution to a puzzle.

Step 1: Since the only combination for 23 into three cells is 6+8+9 we put 6, 8 and 9 in each answer cell for 23.

Step 2: For 9 across we remove the 9 in the second cell since 0+9=9 contains a zero. We then put 1 and 3 in the first cell (1+8=9 and 3+6=9).

Step 3: For 6 down we remove the 3 in the first cell since 3+3=6 contains duplicates. That leaves us with 1 in the first cell so we put 5 in the second cell (1+5=6).

Step 4: For 9 across we put 8 in the second cell (1+8=9). We then remove the 8 from the second and third cells of 23 since duplicates are not allowed.

Step 5: For 17 across we know the only valid combination is 5+9+3 since 5+6+6 contains duplicates.

Step 6: We can now finish the puzzle (8+9+6=23, 6+7=13 and 3+7=10).

Tips

Tip 1

Start with clues that have only one combination such as 3=1+2, 4=1+3, 16=7+9, 17=8+9, 6=1+2+3, and so on.

Tip 2

Take advantage of the possible combinations area located above the puzzle:

This area shows all possible combinations for the vertical and horizontal clues for the current cell. Numbers already entered in the answer cells for a clue will be blue. Combinations no longer valid are grayed out. Looking at the example above, we can determine the remaining two cells for the vertical clue (20) will be 7+9.

Tip 3

Use fast select and drag to improve your speed.Fast select refers to selecting a single number regardless of how many numbers are currently selected within a cell. To fast select right click a number (mouse), touch and hold a number for 1 second (mobile) or press and hold a key for 1 second (physical keyboard).

Use drag to select multiple numbers at once within a cell. To drag press and hold the left mouse button on a number then drag (mouse) or touch a number then drag (mobile). This works with all control types including the on-screen keyboard.