Random Post
Recent Posts
- Enigma 767: Safety in numbers
- BrainTwister #18: The arithmetical two-step
- Enigma 774: Sting in the tail
- BrainTwister #17: Semi-one numbers
- Enigma 773: Duodecimal
- BrainTwister #16: Order, order!
- Enigma 772: Have you seen the trailer?
- BrainTwister #15: Domino strips
- Enigma 771: Cross the island
- BrainTwister #14: Factor graphs
Recent Comments
Archives
Categories
- article (11)
- braintwister (18)
- enigma (1,717)
- enigma-book-1982 (70)
- headscratchers-book-2023 (70)
- microteasers-book-1986 (11)
- misc (7)
- project euler (2)
- puzzle (90)
- puzzle# (249)
- site news (83)
- sphinx (4)
- tantalizer (254)
- tantalizer-book-1970 (40)
- teaser (7)
- today (1)
Site Stats
- 347,151 hits
This Python 3 program runs in 41ms.
Solution: The remaining letters in each row, from top to bottom, are: G, B, A, E, F, C, H, I, D.
There is only one solution for the grid, shown below:
For 9 letters each occuring 3 times, it is feasible to do a brute force search of the 3**9 = 19683 possible options of distinct letters, but this solution wouldn’t be scalable.