even prettier!
Haldean Brown
3 years ago
| 1 | 1 | import Data.Char |
| 2 | 2 | import Data.Function |
| 3 | 3 | |
| 4 | collapse1 (a:b:ss) = if toLower a == toLower b && a /= b then collapse1 ss else a:(collapse1 $ b:ss) | |
| 4 | collapse1 (a:b:ss) | |
| 5 | | toLower a == toLower b && a /= b = collapse1 ss | |
| 6 | | otherwise = a:(collapse1 $ b:ss) | |
| 5 | 7 | collapse1 s = s |
| 6 | 8 | collapse s = let cs = collapse1 s in if cs == s then s else collapse cs |
| 7 | 9 | main = readFile "input.txt" >>= (collapse >>> length >>> subtract 1 >>> print) |