Compdoku 9x9 #3 - Other names are Hikaku (Puzzlephil), Greater-Than Sudoku, Comparison Sudoku.
The puzzle is a 9x9 square, consisting of 9 smaller blocks, divided in turn into 9 cells.
The task is to enter numbers from 1 to 9 in the puzzle cells so that in each horizontal row, in each vertical column and in each block, each number occurs only once.
This version of sudoku does not contain numbers in the task - only comparison signs (“>” and “<”), showing the ratio of numbers in adjacent cells.