Sudoku 16 Puzzle

[Features]
★ Supports creation and solving of Sudoku with various block sizes.
★ Provides a difficulty rating for Sudoku.
(Provides rating and total difficulty calculated based on Sudoku Explainer)
★ Sudoku stair
(Sudoku blocks are classified according to size, and grades are given based on solving records.)
★ Sudoku AI Battle
(If there is no input from the user for a certain period of time, AI will input automatically.)

[Supported block sizes]
★ 2x2 Block (4 Numbers)
★ 2x3 Block (6 Numbers)
★ 2x4 Block (8 Numbers)
★ 3x3 Block (9 Numbers)
★ 3x4 Block (12 Numbers)
★ 3x5 Block (15 Numbers)
★ 4x4 Block (16 Numbers)

[Supported Sudoku types]
※ The Sudoku types refer to Richard Stolk's 'Sudoku Variants Series'.
★ Classic Sudoku : This is the most common type of Sudoku.
★ Odd-Even Sudoku : You will be given a space where only odd numbers (or even numbers) can fit.
★ No-Touch Sudoku : The same number cannot be placed in diagonally adjacent cells.
★ Number Group Sudoku : For every cell, only numbers within a certain range can be entered.
★ Diagonal Sudoku : The same number cannot fit in both diagonal areas.

[Caution]
★ Setting the blank percentage to high increases creation time.