**Sudoku gadget**

# The puzzle

SuDoku is one of most popular puzzles in the world. SuDoku is a logic-based,number-placement puzzle. The objective is to fill a 9×9 grid so that each column, each row, and each of the nine 3×3 boxes (also called blocks or regions) contains the digits from 1 to 9 only one time each. The game provides a partially completed grid.# How to play - Rules of SuDoku

- Sudoku is a 9 x 9 grid. It is divided into 9 regions.
- The numbers 1 till 9 must be placed only once in:
- Each column (vertical)
- Each row (horizontal)
- Each region (3x3 sub-grid)

- Before starting there are always numbers filled in the diagram.
- The puzzle is difficult to solve, when the initial numbers are less.