SUDOKU

Write a number from 1 to 9 into each empty square in the grid so that every number from 1 to 9 appears exactly once in each horizontal row, each vertical column, and each 3×3 block.
  73      52  
68          91
5      3      8
      7  3      
    1  9  4    
      5  6      
8      5      7
71          4  
  35      1  9
* Easy