Here we list some of these puzzles and their solutions using the program. They are graded in order of difficulty easiest to difficult to "not fun".

(See list of heuristics here.)

File: `wildcatjan17`
Solved in 73 steps. Uses only Heuristic 1: Simple row, column or 3 x 3 area inconsistency/insufficiency. |

File: `wildcatjan18`
Solved in 81 steps. Uses only Heuristic 1: Simple row, column or 3 x 3 area inconsistency/insufficiency. |

File: `dtfeb19`
Solved in 178 steps.
This is from the Only requires Heuristics 1 and 2, i.e. simple consistency check for rows, columns and 3x3 areas, and the subset cover idea. |

File: `v2155141`
Solved in 196 steps.
It has only one step that is difficult (line 56). (See the description here.) To get past line 55, it employs the boosted version of Heuristic 1 plus an assist from Heuristic 4. |

File: `challenge2`
Solved in 133 steps.
This is Challenge 2 from Sudoku Solver by Logic. (See also the harder Challenge 1 below.) This puzzles requires multiple instances of Heuristic 1+ before succumbing to direct elimination methods. However, all of the inference chains are relatively easy to follow as they require no more than two pivots. |

File: `challenge1`
Solved in 229 steps.
This is Challenge 1 from Sudoku Solver by Logic. Under the default setting, the program gets to step 84 making liberal use of Heuristic 1+, i.e. chaining. To proceed further, you must set the 1+ limit, the length of the chains the program is allowed to use to derive a contradiction, to unlimited. |

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