Solution to Sudoku no 688

Sudoku no 688 (Easy)

Our younger son created this puzzle using a Javascript program which he wrote himself.

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Solution to Sudoku no 687

Sudoku no 687 (Moderate)

Our younger son created this puzzle using a Javascript program which he wrote himself.

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Solution to Sudoku no 686

Sudoku no 686 (Extreme)

This puzzle has a Hodoku grade of 18788.

Andrew Stuart's solver was unable to grade it.

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Solution to Sudoku no 685

Sudoku no 685 (Diabolical)

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Solution to Sudoku no 684

Sudoku no 684 (Tough)

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Solution to Sudoku no 683

Sudoku no 683 (Easy)

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Solution to Sudoku no 682

Sudoku no 682 (Extreme)

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Solution to Sudoku no 681

Sudoku no 681 (Diabolical)

 

 

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Solution to Sudoku no 680

Sudoku no 680 (Tough)

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Solution to Sudoku no 679

Sudoku no 679 (Easy)

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Solution to Sudoku no 678

Sudoku no 678 (Easy)

Our younger son produced this puzzle using a Javascript program which he wrote himself:

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Solution to Sudoku no 677

Sudoku no 677 (Diabolical)

Our younger son created this puzzle using a Javascript program which he wrote himself:

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Solution to Sudoku no 676

Sudoku no 676 (Extreme)

Please comment below if you manage to solve this sudoku puzzle.

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Solution to Sudoku no 675

Sudoku no 675 (Moderate)

Our younger son created this puzzle using a Javascript program which he wrote himself:

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Solution to Sudoku no 674

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Sudoku no 674 (Diabolical)

Our younger son created this sudoku puzzle using a Javascript program which he wrote himself:

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Solution to Sudoku no 673

Sudoku no 673 (Easy)

Our younger son created this sudoku puzzle using a Javascript program which he wrote himself:

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Solution to Sudoku no 672

Sudoku no 672 (Tough)

Our younger son created this puzzle using a Javascript program which he wrote himself:

This puzzle has a Hodoku grade of Hard (1038). If you enjoy it there are 400 more in my book, all with a grade between Hard (1000) and Hard (1999). You can order it here.

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Solution to Sudoku no 671

Sudoku no 671 (Tough)

Our younger son created this puzzle using a Javascript program which he wrote himself:

I used Andrew Stuart's site to check this puzzle and it graded it as 305. The solve path involved two uses of pointing pairs and two of simple colouring. I then ran it through Hodoku, which gave it a grade of Hard (554) so it would not have made it into my book of tough puzzles as they all have a Hodoku grade between Hard (1000) and Hard (1999). You can order it here. This link takes you to Amazon UK. If you go to your local Amazon outlet and search for "tough sudoku" + "andrew reid" you should find it there too.

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Solution to Sudoku no 670

Sudoku no 670 (Tough)

Our younger son created this puzzle using a Javascript program which he wrote himself:

It has a Hodoku grade of Hard (1054). If you enjoy puzzles like this there are 400 more in my book, which has sudokus with a Hodoku grade between Hard (1000) and Hard (1999). You can order it here.

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Solution to Sudoku no 669

Sudoku no 669 (Extreme)

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Solution to Sudoku no 668

Sudoku no 668 (Tough)

This puzzle has a similar grade to the 400 in my book.

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Solution to Sudoku no 667

Sudoku no 667 (Easy)

Our younger son created this puzzle using a Javascript program which he wrote himself.

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Solution to Sudoku no 666

Sudoku no 666 (Diabolical)

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Solution to Sudoku no 665

Sudoku no 665 (Diabolical)

This puzzle has a Hodoku grade of Hard (1376) so it would have qualified for inclusion in my book as all the puzzles there have a Hodoku grade between Hard (1000) and Hard (1999).

Andrew Stuart gives it a grade of 201 (Very Hard) on his main page but calls it Diabolical when you look at the solve path.

Please click here if you would like to see my book. Amazon shows you the first 18 puzzles in the preview.

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Solution to Sudoku no 664

Sudoku no 664 (Diabolical)

I created this puzzle just now. I was trying to create an extreme one but, after 75 attempts I had not found what I was looking for so I chose this one instead. It has a Hodoku grade of Hard (1508) so it is typical of the puzzles in my book, which all have a Hodoku grade between Hard (1000) and Hard (1999).

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