| Magic Square|
Sudoku - a puzzle that has received tremendous popularity recently. Its rule is simple: given a square of 81 cells, which in turn is composed of 9 squares by 9 squares. We need to put in the cells from 1 to 9 so that each row and column of a large square, and within each of the small number of squares will not be repeated. Some cells at the beginning is full, the rest need to fill in yourself, using logic and shrewd calculation.