Problem 424

[LarryBlake]

Two rules questions:

1. Can an answer (across or down) contain duplicate digits?
2. Can an answer (across or down) contain a zero?

I suspect the answers are both no, but please confirm.

[AVN]

I haven't solved this problem (it's out of my league at the moment), but I have solved lots of Kakuro puzzles.
I can confirm that the answer on both questions is indeed no.

[CFB]

I am devastated!!! So near to being in the first 100.
I get the correct solution for the first puzzle, and I get the correct sum for puzzles 1 to 10, but my sum for puzzles 1 to 200 is incorrect.
Can anyone give me a hint as to where my error might be? It is not an integer overflow problem.
Thanks
Colin

[Marcus_Andrews]

Ensure that each equation does not contain any repeated digits or zeroes. It's possible to sometimes get the right number (i.e. the A-J identifier) even if these constraints aren't met 100%, but this won't work for all cases.

Other than that, this is an input-file problem -- so it may be something "silly" like your code only parsing 199 instead of 200 puzzles because of a one-off line-reading error, etc.

I am devastated!!! So near to being in the first 100.
I get the correct solution for the first puzzle, and I get the correct sum for puzzles 1 to 10, but my sum for puzzles 1 to 200 is incorrect.
Can anyone give me a hint as to where my error might be? It is not an integer overflow problem.
Thanks
Colin

[kaifeng]

I found more then one solution even for the sample puzzle; is that possible?
Here is one of my solutions. The difference in show in red.

424.png

[TheEvil]

In the second row you have two 9's. Every row and coloumn must contain pairwise distinct digits, as far as I know.

[whakamaru]

I can do them in the newspaper, easily, but can I translate that logic into lines of code? Probably not.

[tim-brown]

I am finding two (or more) distinct solutions to some puzzles. e.g. line 9 below.

I see no duplicated numbers, and as far as my arithmetic goes, all of the sums add up.
But the two solutions give different contributions to the "sum of the answers ..."

Am I missing a rule here?

(Line 8 has the same problem; but it has (hXX,vXX) combinations, so this is simpler.)

Code: Select all

7,X,(vBB),(vBD),X,X,X,X,(hBB),C,E,(vEE),(vEC),X,X,(hBC),O,O,O,O,X,X,X,(hEF),H,O,A,(vJ),X,X,X,(hBD),O,O,O,(vI),X,X,(hBE),F,O,O,O,X,X,X,X,(hG),O,O

Code: Select all

[8,1,9,0,2,4,5,7,3,6]
X        v(BB=11) v(BD=10) X        X        X      X
h(BB=11) 9        2        v(EE=22) v(EC=29) X      X
h(BC=19) 2        1        7        9        X      X
X        h(EF=24) 7        9        8        v(J=6) X
X        X        h(BD=10) 2        5        3      v(I=3)
X        X        h(BE=12) 4        7        1      0
X        X        X        X        h(G=5)   2      3
=8190245736

[8,1,9,0,2,4,5,7,6,3]
X        v(BB=11) v(BD=10) X        X        X      X
h(BB=11) 9        2        v(EE=22) v(EC=29) X      X
h(BC=19) 2        1        7        9        X      X
X        h(EF=24) 7        9        8        v(J=3) X
X        X        h(BD=10) 2        7        1      v(I=6)
X        X        h(BE=12) 4        5        2      1
X        X        X        X        h(G=5)   0      5
=8190245763

[Marcus_Andrews]

Zeroes are not allowed.

[tim-brown]

Zeroes are not allowed.

Thanks for that. I's not clear on the problem description (IMHO).

Anyhow, here's hoping that it gets me unique answers.

[LarryBlake]

I get xxxxxxxx through 5. Is that correct? For some reason, my answer for 10 is wrong.

EDIT: Found my mistake. Correct answer for 5 is 35673704235.

[ludopulles]

In the second row you have two 9's. Every row and coloumn must contain pairwise distinct digits, as far as I know.

So can someone confirm that the second puzzle on https://www.conceptispuzzles.com/index. ... kuro/rules actually is not allowed since 1 is used twice in the third column but in different 'blocks'?

[ludopulles]

My error was because I accepted zeros. I have it right now.

You may have the same digits in a row or column, as long as the digits in each block are distinct.

[yourmaths]

I just finished this problem. I found it a fun and satisfying problem, but there are a lot of things that can (and did) go wrong. The problem page is pretty vague on the rules of kakuro (and multiple people mention in the forum that they found the specs quite confusing), so I'm hoping the following will help future solvers:

For the complete-grid kakuro (right-hand diagram on the problem page), a "block" is a contiguous row of horizontal or vertical squares. Blocks must add to the totals given. Zeros are not allowed in the grid. Within each block, each digit must be different.

However, the same digit can appear in a row or column (e.g. 1 appears twice in the fourth column of the example on the problem page), so long as it doesn't appear in the same block.

Finally, this is not a rule of kakuro, but, according to my calculations, each of the 200 puzzle strings has a unique solution, so if you're getting more than one solution, your algorithm is doing something wrong. Obviously each puzzle string will have a unique letter-digit mapping so that the final answer is well defined, but for the correct letter-digit mapping, there is a unique complete-grid solution as well.

Hope that helps.