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.

Sudoku grader and solver

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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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