I developed the solution to the Drive Ya Nuts puzzle. There are 7! * 6^6 = 235,146,240 ways that the pieces can be arranged on the board. I solved the physical version years ago, but I thought it would be fun to go back and solve it programmatically.
The solution uses recursive depth-first search to find mismatches as quickly as possible. This ended up being considerably faster than checking every permutation of all pieces' placement.
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/ 6 \
/ 1 5 \
----- \ 2 4 / -----
/ 4 \ \ 3 / / 6 \
/ 6 2 \ ----- / 4 2 \
\ 1 5 / ----- \ 1 3 /
\ 3 / / 3 \ \ 5 /
----- / 5 1 \ -----
----- \ 4 6 / -----
/ 3 \ \ 2 / / 5 \
/ 2 4 \ ----- / 6 3 \
\ 1 5 / ----- \ 1 2 /
\ 6 / / 2 \ \ 4 /
----- / 5 1 \ -----
\ 6 4 /
\ 3 /
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