Copyright © Richard C Smith 2007 - 2012.
This work is licenced under a Creative Commons Licence.
Select the puzzle geometry that you would like to solve from the drop-down list below. Click on "New" to change the puzzle geometry or to clear an existing grid.
Here is the result of running the solver on the grid that you entered.
2 | 1 | 5 | 8 | 7 | 6 | 9 | 4 | 3 |
6 | 7 | 8 | 3 | 9 | 4 | 2 | 1 | 5 |
| 3 | 4 | 9 | 1 | 2 | 5 | 8 | 7 | 6 |
5 | 8 | 7 | 4 | 3 | 2 | 1 | 6 | 9 |
| 4 | 6 | 3 | 9 | 8 | 1 | 7 | 5 | 2 |
1 | 9 | 2 | 6 | 5 | 7 | 3 | 8 | 4 |
| 8 | 2 | 6 | 7 | 4 | 3 | 5 | 9 | 1 |
| 7 | 3 | 4 | 5 | 1 | 9 | 6 | 2 | 8 |
9 | 5 | 1 | 2 | 6 | 8 | 4 | 3 | 7 |
Solver ran for 23.40 seconds
Found cell e2 with single value 6 Removing value 6 from column, row and block for cell e2 Completed 1 of 81 cells. Found cell d2 with single value 8 Removing value 8 from column, row and block for cell d2 Completed 2 of 81 cells. Found cell i5 with single value 6 Removing value 6 from column, row and block for cell i5 Completed 3 of 81 cells. Found cell g4 with single value 7 Removing value 7 from column, row and block for cell g4 Completed 4 of 81 cells. Found cell e3 with single value 3 Removing value 3 from column, row and block for cell e3 Completed 5 of 81 cells. Found cell g1 with single value 8 Removing value 8 from column, row and block for cell g1 Completed 6 of 81 cells. Found cell e1 with single value 4 Removing value 4 from column, row and block for cell e1 Completed 7 of 81 cells. Found cell i4 with single value 2 Removing value 2 from column, row and block for cell i4 Completed 8 of 81 cells. Found cell d3 with single value 7 Removing value 7 from column, row and block for cell d3 Completed 9 of 81 cells. Found cell a8 with single value 4 Removing value 4 from column, row and block for cell a8 Completed 10 of 81 cells. Found cell h8 with single value 2 Removing value 2 from column, row and block for cell h8 Completed 11 of 81 cells. Found cell b9 with single value 5 Removing value 5 from column, row and block for cell b9 Completed 12 of 81 cells. Found cell d4 with single value 4 Removing value 4 from column, row and block for cell d4 Completed 13 of 81 cells. Found cell i2 with single value 5 Removing value 5 from column, row and block for cell i2 Completed 14 of 81 cells. Found cell i6 with single value 8 Removing value 8 from column, row and block for cell i6 Completed 15 of 81 cells. Found cell b5 with single value 9 Removing value 9 from column, row and block for cell b5 Completed 16 of 81 cells. Found cell c1 with single value 3 Removing value 3 from column, row and block for cell c1 Completed 17 of 81 cells. Found cell c8 with single value 7 Removing value 7 from column, row and block for cell c8 Completed 18 of 81 cells. Found cell h1 with single value 7 Removing value 7 from column, row and block for cell h1 Completed 19 of 81 cells. Found cell f8 with single value 8 Removing value 8 from column, row and block for cell f8 Completed 20 of 81 cells. Found cell c6 with single value 5 Removing value 5 from column, row and block for cell c6 Completed 21 of 81 cells. Found cell d7 with single value 1 Removing value 1 from column, row and block for cell d7 Completed 22 of 81 cells. Found cell a5 with single value 7 Removing value 7 from column, row and block for cell a5 Completed 23 of 81 cells. Found cell b2 with single value 7 Removing value 7 from column, row and block for cell b2 Completed 24 of 81 cells. Found cell h9 with single value 8 Removing value 8 from column, row and block for cell h9 Completed 25 of 81 cells. Found cell e5 with single value 8 Removing value 8 from column, row and block for cell e5 Completed 26 of 81 cells. Found cell a7 with single value 9 Removing value 9 from column, row and block for cell a7 Completed 27 of 81 cells. Found cell f6 with single value 7 Removing value 7 from column, row and block for cell f6 Completed 28 of 81 cells. Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Removed 2 instances of value 1 from cells d4, f4, d5, f5, d6, f6 Removed 4 instances of value 3 from cells g7, h7, g8, h8, g9, h9 Removed 3 instances of value 6 from cells a2, b2, c2, a3, b3, c3 End of pass: removed 9 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell a2 contains the pair of values 1, 2 Testing value 1 in a2 Testing value 2 in a2 Cell e8 contains the pair of values 5, 9 Testing value 5 in e8 Testing value 9 in e8 Cell i1 contains the pair of values 1, 9 Testing value 1 in i1 Testing value 9 in i1 Cell c4 contains the pair of values 1, 6, 8 Testing value 1 in c4 Testing value 6 in c4 Testing value 8 in c4 Cell d1 contains the pair of values 2, 5, 9 Testing value 2 in d1 End of pass: removed value 2 from cell d1 as it produces an invalid grid Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Removed 3 instances of value 2 from cells f4, f5, f6, f7, f8, f9 End of pass: removed 3 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell a2 contains the pair of values 1, 2 Testing value 1 in a2 Testing value 2 in a2 Cell d1 contains the pair of values 5, 9 Testing value 5 in d1 Testing value 9 in d1 Cell e8 contains the pair of values 5, 9 Testing value 5 in e8 Testing value 9 in e8 Cell i1 contains the pair of values 1, 9 Testing value 9 in i1 Cell f5 contains the pair of values 3, 5 Testing value 5 in f5 Cell c4 contains the pair of values 1, 6, 8 Testing value 1 in c4 Testing value 6 in c4 Testing value 8 in c4 End of pass: removed value 8 from cell c4 as it produces an invalid grid Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell c4 contains the pair of values 1, 6 Testing value 1 in c4 Testing value 6 in c4 Cell a2 contains the pair of values 1, 2 Testing value 1 in a2 Testing value 2 in a2 Cell d1 contains the pair of values 5, 9 Testing value 5 in d1 Testing value 9 in d1 Cell e8 contains the pair of values 5, 9 Testing value 5 in e8 Testing value 9 in e8 Cell i1 contains the pair of values 1, 9 Testing value 9 in i1 Cell f5 contains the pair of values 3, 5 Testing value 5 in f5 Cell i7 contains the pair of values 3, 4, 7 Testing value 3 in i7 End of pass: removed value 3 from cell i7 as it produces an invalid grid Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell c4 contains the pair of values 1, 6 Testing value 1 in c4 Testing value 6 in c4 Cell a2 contains the pair of values 1, 2 Testing value 1 in a2 Testing value 2 in a2 Cell d1 contains the pair of values 5, 9 Testing value 5 in d1 Testing value 9 in d1 End of pass: removed value 9 from cell d1 as it produces an invalid grid Cell d1 reduced to one value (5) Found cell d1 with single value 5 Removing value 5 from column, row and block for cell d1 Completed 29 of 81 cells. Searching for single candidates End of pass: only cell a3 in this group contains the value 5 Found cell a3 with single value 5 Removing value 5 from column, row and block for cell a3 Completed 30 of 81 cells. Searching for single candidates End of pass: only cell a4 in this group contains the value 8 Found cell a4 with single value 8 Removing value 8 from column, row and block for cell a4 Completed 31 of 81 cells. Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Removed 2 instances of value 9 from cells f4, f5, f6, f7, f8, f9 End of pass: removed 2 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Processing chain of cells a1, b1, a2 for values 6, 1, 2 to remove from cells c1, b2, c2, a3, b3, c3 End of pass: removed 6 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell c4 contains the pair of values 1, 6 Testing value 1 in c4 Testing value 6 in c4 End of pass: removed value 6 from cell c4 as it produces an invalid grid Cell c4 reduced to one value (1) Found cell c4 with single value 1 Removing value 1 from column, row and block for cell c4 Completed 32 of 81 cells. Searching for single candidates End of pass: only cell e6 in this group contains the value 1 Found cell e6 with single value 1 Removing value 1 from column, row and block for cell e6 Completed 33 of 81 cells. Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Removed 3 instances of value 6 from cells a7, b7, a8, b8, a9, b9 Removed 1 instances of value 2 from cells d7, f7, d8, f8, d9, f9 End of pass: removed 4 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Processing chain of cells e4, e8 for values 9, 5 to remove from cells e1, e2, e3, e5, e6, e7, e9 End of pass: removed 2 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell a2 contains the pair of values 1, 2 Testing value 1 in a2 Testing value 2 in a2 End of pass: removed value 2 from cell a2 as it produces an invalid grid Cell a2 reduced to one value (1) Found cell a2 with single value 1 Removing value 1 from column, row and block for cell a2 Completed 34 of 81 cells. Searching for single candidates End of pass: only cell b8 in this group contains the value 1 Found cell b8 with single value 1 Removing value 1 from column, row and block for cell b8 Completed 35 of 81 cells. Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Removed 1 instances of value 2 from cells d1, e1, f1, g1, h1, i1 End of pass: removed 1 values from cells Searching for single candidates Search for single candidates unsuccessful Searching for candidate lines Search for candidate lines unsuccessful Searching for naked pairs / triples / etc Search for naked pairs / triples / etc. unsuccessful Searching for hidden pairs / triples / etc Search for hidden pairs / triples / etc. unsuccessful Looking for X-Wing, etc patterns Search for X-Wing, etc patterns unsuccessful Looking for chains of values using simple coloring Search with simple coloring unsuccessful Looking for chains of values using multi coloring (single value type) Search with multi coloring unsuccessful Looking for forcing chains Search for forcing chains unsuccessful Looking for values which produce an invalid grid (Nishio) Cell i7 contains the pair of values 4, 7 Testing value 4 in i7 Testing value 7 in i7 Cell b3 contains the pair of values 4, 8 Testing value 4 in b3 End of pass: removed value 4 from cell b3 as it produces an invalid grid Cell b3 reduced to one value (8) Found cell b3 with single value 8 Removing value 8 from column, row and block for cell b3 Completed 36 of 81 cells. Searching for single candidates End of pass: only cell b6 in this group contains the value 4 Found cell b6 with single value 4 Removing value 4 from column, row and block for cell b6 Completed 37 of 81 cells. Cell c5 reduced to one value (2) Found cell c5 with single value 2 Removing value 2 from column, row and block for cell c5 Completed 38 of 81 cells. Cell c9 reduced to one value (6) Cell d5 reduced to one value (3) Found cell c9 with single value 6 Removing value 6 from column, row and block for cell c9 Completed 39 of 81 cells. Cell c7 reduced to one value (8) Found cell c7 with single value 8 Removing value 8 from column, row and block for cell c7 Completed 40 of 81 cells. Found cell d5 with single value 3 Removing value 3 from column, row and block for cell d5 Completed 41 of 81 cells. Cell d9 reduced to one value (9) Cell f5 reduced to one value (5) Found cell d9 with single value 9 Removing value 9 from column, row and block for cell d9 Completed 42 of 81 cells. Cell d8 reduced to one value (6) Cell e8 reduced to one value (5) Found cell d8 with single value 6 Removing value 6 from column, row and block for cell d8 Completed 43 of 81 cells. Cell d6 reduced to one value (2) Found cell d6 with single value 2 Removing value 2 from column, row and block for cell d6 Completed 44 of 81 cells. Found cell e8 with single value 5 Removing value 5 from column, row and block for cell e8 Completed 45 of 81 cells. Cell e4 reduced to one value (9) Cell g8 reduced to one value (9) Found cell e4 with single value 9 Removing value 9 from column, row and block for cell e4 Completed 46 of 81 cells. Found cell g8 with single value 9 Removing value 9 from column, row and block for cell g8 Completed 47 of 81 cells. Cell g6 reduced to one value (3) Cell i8 reduced to one value (3) Found cell g6 with single value 3 Removing value 3 from column, row and block for cell g6 Completed 48 of 81 cells. Cell h6 reduced to one value (9) Cell h4 reduced to one value (5) Cell a6 reduced to one value (6) Found cell h6 with single value 9 Removing value 9 from column, row and block for cell h6 Completed 49 of 81 cells. Found cell h4 with single value 5 Removing value 5 from column, row and block for cell h4 Completed 50 of 81 cells. Cell f4 reduced to one value (6) Found cell f4 with single value 6 Removing value 6 from column, row and block for cell f4 Completed 51 of 81 cells. Cell b4 reduced to one value (3) Found cell b4 with single value 3 Removing value 3 from column, row and block for cell b4 Completed 52 of 81 cells. Cell b7 reduced to one value (2) Found cell b7 with single value 2 Removing value 2 from column, row and block for cell b7 Completed 53 of 81 cells. Cell a9 reduced to one value (3) Cell e7 reduced to one value (7) Cell b1 reduced to one value (6) Found cell a9 with single value 3 Removing value 3 from column, row and block for cell a9 Completed 54 of 81 cells. Cell f9 reduced to one value (4) Found cell f9 with single value 4 Removing value 4 from column, row and block for cell f9 Completed 55 of 81 cells. Cell g9 reduced to one value (1) Cell f7 reduced to one value (3) Found cell g9 with single value 1 Removing value 1 from column, row and block for cell g9 Completed 56 of 81 cells. Cell g5 reduced to one value (4) Cell i9 reduced to one value (7) Found cell g5 with single value 4 Removing value 4 from column, row and block for cell g5 Completed 57 of 81 cells. Cell h5 reduced to one value (1) Cell g2 reduced to one value (2) Found cell h5 with single value 1 Removing value 1 from column, row and block for cell h5 Completed 58 of 81 cells. Found cell g2 with single value 2 Removing value 2 from column, row and block for cell g2 Completed 59 of 81 cells. Cell g3 reduced to one value (6) Cell f2 reduced to one value (9) Found cell g3 with single value 6 Removing value 6 from column, row and block for cell g3 Completed 60 of 81 cells. Cell g7 reduced to one value (5) Cell h3 reduced to one value (4) Found cell g7 with single value 5 Removing value 5 from column, row and block for cell g7 Completed 61 of 81 cells. Found cell h3 with single value 4 Removing value 4 from column, row and block for cell h3 Completed 62 of 81 cells. Cell c3 reduced to one value (9) Cell h7 reduced to one value (6) Cell h2 reduced to one value (3) Found cell c3 with single value 9 Removing value 9 from column, row and block for cell c3 Completed 63 of 81 cells. Cell c2 reduced to one value (4) Cell i3 reduced to one value (1) Found cell c2 with single value 4 Removing value 4 from column, row and block for cell c2 Completed 64 of 81 cells. Found cell i3 with single value 1 Removing value 1 from column, row and block for cell i3 Completed 65 of 81 cells. Cell f3 reduced to one value (2) Cell i1 reduced to one value (9) Found cell f3 with single value 2 Removing value 2 from column, row and block for cell f3 Completed 66 of 81 cells. Found cell i1 with single value 9 Removing value 9 from column, row and block for cell i1 Completed 67 of 81 cells. Cell f1 reduced to one value (1) Found cell f1 with single value 1 Removing value 1 from column, row and block for cell f1 Completed 68 of 81 cells. Found cell h7 with single value 6 Removing value 6 from column, row and block for cell h7 Completed 69 of 81 cells. Found cell h2 with single value 3 Removing value 3 from column, row and block for cell h2 Completed 70 of 81 cells. Found cell f2 with single value 9 Removing value 9 from column, row and block for cell f2 Completed 71 of 81 cells. Found cell i9 with single value 7 Removing value 7 from column, row and block for cell i9 Completed 72 of 81 cells. Cell e9 reduced to one value (2) Cell i7 reduced to one value (4) Found cell e9 with single value 2 Removing value 2 from column, row and block for cell e9 Completed 73 of 81 cells. Found cell i7 with single value 4 Removing value 4 from column, row and block for cell i7 Completed 74 of 81 cells. Found cell f7 with single value 3 Removing value 3 from column, row and block for cell f7 Completed 75 of 81 cells. Found cell e7 with single value 7 Removing value 7 from column, row and block for cell e7 Completed 76 of 81 cells. Found cell b1 with single value 6 Removing value 6 from column, row and block for cell b1 Completed 77 of 81 cells. Cell a1 reduced to one value (2) Found cell a1 with single value 2 Removing value 2 from column, row and block for cell a1 Completed 78 of 81 cells. Found cell a6 with single value 6 Removing value 6 from column, row and block for cell a6 Completed 79 of 81 cells. Found cell i8 with single value 3 Removing value 3 from column, row and block for cell i8 Completed 80 of 81 cells. Found cell f5 with single value 5 Removing value 5 from column, row and block for cell f5 Completed 81 of 81 cells.
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Copyright © Richard C Smith 2007 - 2012.
This work is licenced under a Creative Commons Licence.