Sudoku #3774

Complexity: Extremely Hard

 Fun Fact About Sudoku
The oldest known puzzle is a dissection of a square mentioned by Archimedes around 250BC.

Enter numbers into the empty cells so that each row, column and 3x3 box contains the numbers 1 to 9.

8 9 2 5 1 6
4 6 3 9 2 8
3 2 8
6 4 2 5 1
1 4 3 6 2
9 5 6
5 4 8 6 1 2
6 9 3 5 1 4