Solving Kakuro: (Overlapping Cells)

This technique can be used effectively once you learn how to use it correctly.

Take a look at Puzzle No.9


Using this technique, you can directly find out the number in the marked cell.


The sum of the five marked cells is 12 + 21 = 33 (Using the column sums).


But, the sum of the four marked cells is 11 + 16 = 27 (Using the row sums).


Simple subtraction, and you get 33 - 27 = 6 in the marked cell.

Use this technique and you are bound to improve your solving time!

Other Solving Techniques

14 comments:

  1. Tejal PhatakJanuary 3, 2011 at 10:33 PM

    I never used this till today!

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  2. Rohan RaoJanuary 3, 2011 at 10:37 PM

    Now try using it. Master it soon, IPC rounds are starting this week!

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  3. Prasanna SeshadriJanuary 3, 2011 at 10:43 PM

    I haven't used either :O top post Ro.

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  4. Rohan RaoJanuary 3, 2011 at 10:44 PM

    Thanks Pras. Try it out, you'll definitely love it, especially with IPC round the corner.

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  5. DebJanuary 4, 2011 at 12:22 PM

    It can be extended to multiple cells too. You should post one example.

    Good posts Rohan, on these simple, but effective techniques.

    I'm still surprised that Tejal didn't use it yet.

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  6. UnknownJanuary 4, 2011 at 12:41 PM

    cool technique....ur methods proving to be quite useful for me...1 query...on 7th jan , in the elimination rounds, can 1 person participate in both ISC and IPC round 1

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  7. UnknownJanuary 4, 2011 at 12:42 PM

    do u know what kind of puzzles will be there in round 1 of IPC??

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  8. Rohan RaoJanuary 4, 2011 at 4:32 PM

    @Deb
    Yes, I'll post about multiple cells too.

    @Natraj
    You will find complete information about IPC on http://www.logicmastersindia.com/IPC2011/home.asp
    You can post your queries on the forum.

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  9. AnonymousJanuary 4, 2011 at 6:28 PM

    I too only realised you could do this with kakuro recently. Most kakuro I see never seem to need it. Indeed, when I design kakuro of my own I specifically design the grid so that you cannot use this technique (and indeed analogously for killer sudoku, where I think too much cage addition is a completely lazy and lame way of making a puzzle "hard"...)

    Tom.C

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  10. Rohan RaoJanuary 4, 2011 at 6:40 PM

    This technique is rarely seen in really hard Kakuros, that I agree with you. For medium ones, it could be a great starting point for beginners (I was one few months back! :-) )

    Though I must admit that I have used this technique a couple of times in tough Kakuros, but generally with two (or more) protruding cells, like a difference of 4 which gives you a 1-3 combination.

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  11. Rajesh KumarJanuary 16, 2011 at 5:44 PM

    Nice Technique. This technique is very helpful while solving tough Kakuro puzzle.

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  12. OHOAWFebruary 10, 2011 at 11:51 PM

    wow, this is a good technique.. Never thought of ths till now!!

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  13. UnknownApril 21, 2011 at 8:19 PM

    This is Top Class, Rohan! Never used it till date. Thanks for the share :)

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  14. OHOAWJune 7, 2011 at 1:50 PM

    Really cool technique!

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