Rules:

Less Than (or Greater Than) Sudoku has no given clues (digits). Instead, there are "greater than" (>) or "less than" (<) signs between adjacent cells, which signify that the digit in one cell should be greater than or less than another.
The goal is to fill a grid with digits so that each column and each row contain the digits only once.

Puzzle without any blocks is called Latin Square. There are no additional constraints.