output:
(With debugging prints not shown above)
x 7 x x x x 3 9 5 x x 4 x 7 6 x x x 8 x 2 x x 3 x x 6 x 4 8 2 1 x x 3 x x x 7 8 x 5 9 x x x 6 x x 3 4 5 2 x 6 x x 9 x x 8 x 1 x x x 3 2 x 4 x x 4 1 9 x x x x 7 x Starting round 1 => Investigating square at row: 0 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 1 => Investigating square at row: 0 col: 2 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 6 => Investigating square at row: 0 col: 3 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 4 => Investigating square at row: 0 col: 4 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 8 => Investigating square at row: 0 col: 5 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 2 => Investigating square at row: 1 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 3, 5, 9 Solution not found => Investigating square at row: 1 col: 1 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 3, 5, 9 Solution not found => Investigating square at row: 1 col: 3 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 5 Solution not found => Investigating square at row: 1 col: 6 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 2 Solution not found => Investigating square at row: 1 col: 7 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 8 Solution not found => Investigating square at row: 1 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 2, 8 Solution not found => Investigating square at row: 2 col: 1 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 9 Solution not found => Investigating square at row: 2 col: 3 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 5 Solution not found => Investigating square at row: 2 col: 4 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 9 Solution not found => Investigating square at row: 2 col: 6 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 7 Solution not found => Investigating square at row: 2 col: 7 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 4 Solution not found => Investigating square at row: 3 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 9 Solution not found => Investigating square at row: 3 col: 5 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 7, 9 Solution not found => Investigating square at row: 3 col: 6 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 6, 7 Solution not found => Investigating square at row: 3 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 7 => Investigating square at row: 4 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 2, 3 Solution not found => Investigating square at row: 4 col: 1 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 2, 3 Solution not found => Investigating square at row: 4 col: 4 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 6 => Investigating square at row: 4 col: 7 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 4 Solution not found => Investigating square at row: 4 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 4 => Investigating square at row: 5 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 9 => Investigating square at row: 5 col: 2 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 1 => Investigating square at row: 5 col: 3 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 7 => Investigating square at row: 5 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 8 => Investigating square at row: 6 col: 1 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 2, 3, 5 Solution not found => Investigating square at row: 6 col: 2 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 3, 5 Solution not found => Investigating square at row: 6 col: 4 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 4, 5 Solution not found => Investigating square at row: 6 col: 5 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 7 => Investigating square at row: 6 col: 7 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 5 => Investigating square at row: 7 col: 0 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 7 Solution not found => Investigating square at row: 7 col: 1 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 8 Solution not found => Investigating square at row: 7 col: 2 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 5 => Investigating square at row: 7 col: 5 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 1, 8 Solution not found => Investigating square at row: 7 col: 7 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 6 => Investigating square at row: 7 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 9 => Investigating square at row: 8 col: 3 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Guess now: 5, 6 Solution not found => Investigating square at row: 8 col: 4 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 5 => Investigating square at row: 8 col: 5 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 8 => Investigating square at row: 8 col: 6 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 2 => Investigating square at row: 8 col: 8 This square is not known Will guess: 1, 2, 3, 4, 5, 6, 7, 8, 9 Solved: value = 3 Round 1 concluded: 1 7 6 4 8 2 3 9 5 x x 4 x 7 6 x x x 8 x 2 x x 3 x x 6 x 4 8 2 1 x x 3 7 x x 7 8 6 5 9 x 4 9 6 1 7 3 4 5 2 8 6 x x 9 x 7 8 5 1 x x 5 3 2 x 4 6 9 4 1 9 x 5 8 2 7 3 Starting round 2 => Investigating square at row: 1 col: 0 This square is not known Will guess: 3, 5, 9 Guess now: 3, 5 Solution not found => Investigating square at row: 1 col: 1 This square is not known Will guess: 3, 5, 9 Guess now: 3, 5, 9 Solution not found => Investigating square at row: 1 col: 3 This square is not known Will guess: 1, 5 Guess now: 1, 5 Solution not found => Investigating square at row: 1 col: 6 This square is not known Will guess: 1, 2 Solved: value = 1 => Investigating square at row: 1 col: 7 This square is not known Will guess: 1, 8 Solved: value = 8 => Investigating square at row: 1 col: 8 This square is not known Will guess: 2, 8 Solved: value = 2 => Investigating square at row: 2 col: 1 This square is not known Will guess: 5, 9 Guess now: 5, 9 Solution not found => Investigating square at row: 2 col: 3 This square is not known Will guess: 1, 5 Guess now: 1, 5 Solution not found => Investigating square at row: 2 col: 4 This square is not known Will guess: 5, 9 Solved: value = 9 => Investigating square at row: 2 col: 6 This square is not known Will guess: 1, 7 Solved: value = 7 => Investigating square at row: 2 col: 7 This square is not known Will guess: 1, 4 Solved: value = 4 => Investigating square at row: 3 col: 0 This square is not known Will guess: 5, 9 Solved: value = 5 => Investigating square at row: 3 col: 5 This square is not known Will guess: 7, 9 Solved: value = 9 => Investigating square at row: 3 col: 6 This square is not known Will guess: 6, 7 Solved: value = 6 => Investigating square at row: 4 col: 0 This square is not known Will guess: 2, 3 Guess now: 2, 3 Solution not found => Investigating square at row: 4 col: 1 This square is not known Will guess: 2, 3 Guess now: 2, 3 Solution not found => Investigating square at row: 4 col: 7 This square is not known Will guess: 1, 4 Solved: value = 1 => Investigating square at row: 6 col: 1 This square is not known Will guess: 2, 3, 5 Guess now: 2, 3 Solution not found => Investigating square at row: 6 col: 2 This square is not known Will guess: 3, 5 Solved: value = 3 => Investigating square at row: 6 col: 4 This square is not known Will guess: 4, 5 Solved: value = 4 => Investigating square at row: 7 col: 0 This square is not known Will guess: 5, 7 Solved: value = 7 => Investigating square at row: 7 col: 1 This square is not known Will guess: 5, 8 Solved: value = 8 => Investigating square at row: 7 col: 5 This square is not known Will guess: 1, 8 Solved: value = 1 => Investigating square at row: 8 col: 3 This square is not known Will guess: 5, 6 Solved: value = 6 Round 2 concluded: 1 7 6 4 8 2 3 9 5 x x 4 x 7 6 1 8 2 8 x 2 x 9 3 7 4 6 5 4 8 2 1 9 6 3 7 x x 7 8 6 5 9 1 4 9 6 1 7 3 4 5 2 8 6 x 3 9 4 7 8 5 1 7 8 5 3 2 1 4 6 9 4 1 9 6 5 8 2 7 3 Starting round 3 => Investigating square at row: 1 col: 0 This square is not known Will guess: 3, 5 Solved: value = 3 => Investigating square at row: 1 col: 1 This square is not known Will guess: 3, 5, 9 Guess now: 5, 9 Solution not found => Investigating square at row: 1 col: 3 This square is not known Will guess: 1, 5 Solved: value = 5 => Investigating square at row: 2 col: 1 This square is not known Will guess: 5, 9 Solved: value = 5 => Investigating square at row: 2 col: 3 This square is not known Will guess: 1, 5 Solved: value = 1 => Investigating square at row: 4 col: 0 This square is not known Will guess: 2, 3 Solved: value = 2 => Investigating square at row: 4 col: 1 This square is not known Will guess: 2, 3 Solved: value = 3 => Investigating square at row: 6 col: 1 This square is not known Will guess: 2, 3 Solved: value = 2 Round 3 concluded: 1 7 6 4 8 2 3 9 5 3 x 4 5 7 6 1 8 2 8 5 2 1 9 3 7 4 6 5 4 8 2 1 9 6 3 7 2 3 7 8 6 5 9 1 4 9 6 1 7 3 4 5 2 8 6 2 3 9 4 7 8 5 1 7 8 5 3 2 1 4 6 9 4 1 9 6 5 8 2 7 3 Starting round 4 => Investigating square at row: 1 col: 1 This square is not known Will guess: 5, 9 Solved puzzle in 4 rounds 1 7 6 4 8 2 3 9 5 3 9 4 5 7 6 1 8 2 8 5 2 1 9 3 7 4 6 5 4 8 2 1 9 6 3 7 2 3 7 8 6 5 9 1 4 9 6 1 7 3 4 5 2 8 6 2 3 9 4 7 8 5 1 7 8 5 3 2 1 4 6 9 4 1 9 6 5 8 2 7 3