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#1 2019-07-15 06:05:21
- Allerious101
- Guest
futoshiki
Hello
I've partially completed this futoshiki puzzle:
https://ibb.co/yqs5mQr
Does anyone know how to complete it from here? How can i reduce the pencil marks further?
I'm assuming this can be done with logic rather than guessing, but i can't see how i can reduce
the numbers any further.
#2 2019-07-16 10:16:11
- Bob
- Administrator
- Registered: 2010-06-20
- Posts: 10,143
Re: futoshiki
Hi Allerious101
Welcome to the forum.
Yes, it can be done. The key is the number to the left of the 4. It must be a 1 as all the boxes below it contain numbers that are bigger than something.
That means the top row is fixed. If you try a 2 in the box below the 4, you can quickly fill in a lot, but you end up with two 2s in a column. So that must be a 1.
After that all quickly falls into place. In the third row, one of the ends must be a 1 and once that is fixed the last 1 is forced. etc etc.
Hope that does it for you 
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#3 2019-07-17 05:32:38
- Allerious
- Member
- Registered: 2018-08-19
- Posts: 2
Re: futoshiki
Excellent thanks for the help.
It still seems an element of guessing is required then to complete the puzzle even after having the top row completed.
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#4 2019-07-17 12:13:10
- phrontister
- Real Member
- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 4,818
Re: futoshiki
Hi Allerious,
The puzzle can be solved by logic, without any guessing.
Row 1 solves logically, as Bob said, and leads to multiple elimination of duplicates in the lower rows.
From there, eliminating the 2 from R3C2 ('R' = row, 'C' = column) leaves {3,4} in both R3C2 and R3C3, which enables us to eliminate the 3 from R3C1 and R3C4 because the 3 must be in either R3C2 or R3C3.
...etc, etc.
"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson
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