**Puzzles for everybody**

**What is Su Doku?**

Su Doku (or Sudoku,” or ‘Su-doku”) is
a number-placement puzzle based on a square grid, typically
9 squares by 9, giving 81 squares in all. The puzzle
is further divided (by bold gridlines) into 9 boxes
or “regions,” each a square measuring 3 squares by 3.
Figures from 1 to 9 (known as “givens”) are already
inserted in some of the squares; to complete the puzzle,
a player must insert the missing numbers so that each
row, each column, and each region contains the numbers
1 to 9 once and once only, without any repeats. The
level of difficulty depends upon the number of givens
in any puzzle, and the ease with which a player can
compute the missing numbers by the use of logic.