t publications sort their Sudoku puzzles into four or five rating levels, although the cut-off points and the names of the levels vary widely.  Typically, the levels are "easy", "intermediate", and "hard". Extremely difficult puzzles are known as "diabolical" or "evil". An easy puzzle can be solved using only scanning; an intermediate puzzle may take markup to solve; a hard puzzle will usually take analysis.Another approach is to rely on the experience of a group of human test solvers. Puzzles can be published with a median solving time rather than an algorithmically defined difficulty level.Difficulty is a very complex topic, subject to much debate on the Sudoku forums, because it may depend on the concepts and visual representations one is ready to use.Construction[සංස්කරණය]Building a Sudoku puzzle can be performed by predetermining the locations of the givens and assigning them values only as needed to make deductive progress. This technique gives the constructor greater contro