Bondoku Help

Bondoku is a new number placement puzzle that is rapidly growing in popularity. It consists of a 9x9 grid in which number pairs are placed so that each row, column, and 3x3 region contains the numbers 1 through 9.

The Bondoku Puzzle

Figure 1: The Bondoku Puzzle.
Figure 1: The Bondoku Puzzle.

A Bondoku puzzle will have a number of static cells - in Figure 1, the static cells have darker backgrounds.

The puzzle is completed by positioning the available number tiles into the empty cells of the puzzle. In Figure 1, the available number tiles are in the area to the right of the puzzle's grid.

Hint Click on an empty cell to toggle a circle. Use these circles to track the cells on which you are working.

Drag and Drop
Deltazon Bondoku consists of a drag and drop interface.

The drag and drop operation may be different on your computer, but the basic procedure is:

Rotating Tiles

Figure 2: Position a tile in the rotation control.
Figure 2: Position a tile in the rotation control.
Figure 3: Rotate the tile by clicking the rotate button.
Figure 3: Rotate the tile by clicking the rotate button.

The number pairs are on tiles. These tiles can be positioned on the puzzle grid in any orientation.

To rotate a tile, drag and drop the tile to position it in the rotation control as shown in Figure 2.

Click the rotation button. This will rotate the tile 90 degrees in a clockwise direction. The rotated tile in shown in Figure 3.

Solving Bondoku Puzzles

Figure 4: Analyzing rows, columns and regions.
Figure 4: Analyzing rows, columns, and 3x3 regions.

If we analyze the upper left 3x3 region in Figure 4, we see that the numbers 1, 4, 7, and 9 are required to complete that region.

An analysis of the third column shows the numbers 4 and 9 cannot be placed in the two available cells. From this, we can conclude that 4 and 9 must be positioned in the two available cells in the first column.

An analysis of the first two rows shows that the first row already contains a 9 and the second row already contains a 4. Therefore, the 4 must be positioned in the first column, first row and the 9 must be placed in the first column, second row.

This was accomplished in Figure 4 by rotating the 4-9 tile (see Figures 2 and 3) so that the 4 was in the north position and the 9 was in the south position. The tile was then moved (drag and drop) from the rotation control to it's position on the grid.

Completed Bondoku Puzzles

Figure 5: The complete Bondoku Puzzle.
Figure 5: The complete Bondoku Puzzle.

The completed Bondoku puzzle contains the numbers 1 through 9 in every row, column, and 3x3 region as shown in Figure 5.

It is important to note that the number pairs (the tiles) will always span two columns or two rows, and may also span regions.