See: http://qqwing.com/
qqwing <options>
Sudoku solver and generator.
--generate <num> Generate new puzzles
--solve Solve all the puzzles from standard input
--difficulty <diff> Generate only simple, easy, intermediate, expert, or any
--symmetry <sym> Symmetry: none, rotate90, rotate180, mirror, flip, or random
--puzzle Print the puzzle (default when generating)
--nopuzzle Do not print the puzzle (default when solving)
--solution Print the solution (default when solving)
--nosolution Do not print the solution (default when generating)
--stats Print statistics about moves used to solve the puzzle
--nostats Do not print statistics (default)
--timer Print time to generate or solve each puzzle
--notimer Do not print solve or generation times (default)
--count-solutions Count the number of solutions to puzzles
--nocount-solutions Do not count the number of solutions (default)
--history Print trial and error used when solving
--nohistory Do not print trial and error to solve (default)
--instructions Print the steps (at least 81) needed to solve the puzzle
--noinstructions Do not print steps to solve (default)
--log-history Print trial and error to solve as it happens
--nolog-history Do not print trial and error to solve as it happens
--one-line Print puzzles on one line of 81 characters
--compact Print puzzles on 9 lines of 9 characters
--readable Print puzzles in human readable form (default)
--csv Output CSV format with one line puzzles
--help Print this message
--about Author and license information
--version Display current version number
