Merge pull request #47 from folivetti/main

day 14

Author: ianffcs

2020/folivetti/day10/day10.cabal

@@ -15,7 +15,7 @@ extra-source-files:  README.md
 
 executable day10
   hs-source-dirs:      src
-  other-modules:       Algebra
+  other-modules:       Algebra, Representable
   main-is:             Main.hs
   default-language:    Haskell2010
   build-depends:       base >= 4.7 && < 5

2020/folivetti/day10/src/Main.hs

@@ -3,6 +3,7 @@ module Main where
 import Data.List
 import Control.Monad
 import Algebra
+import Representable
 
 genDynTable :: CoAlgebra (ListF Int) [Int]
 genDynTable []     = NilF
@@ -23,6 +24,15 @@ count n jolts (ConsF x xs) = tot : xs
       | (jolts !! ix) - jolt <= 3 = acc + (xs !! (ix-x-1))
       | otherwise                 = 0
 
+f :: Int -> [Int] -> Int -> Int
+f n jolts ix
+  | ix == n-2 = 1
+  | otherwise = sum $ map (f n jolts) rng
+  where
+    rng  = filter (\jx -> (jx < n) && within jx) [ix+1..ix+3]
+    jolt = jolts !! ix
+    within jx = jolts !! jx <= jolt + 3
+
 main :: IO ()
 main = do
   dat <- map read . lines <$> readFile "day10.txt"
@@ -31,5 +41,8 @@ main = do
       n     = length jolts
       n1    = length $ filter (==1) diff
       n3    = length $ filter (==3) diff
+      t :: Stream Int
+      t     = tabulate (f n jolts)
   print $ n1*(n3+1)
   print $ head $ hylo (count n jolts) genDynTable [0 .. length jolts - 2]
+  print $ index t 0

2020/folivetti/day10/src/Representable.hs

@@ -0,0 +1,23 @@
+{-# language TypeFamilies #-}
+module Representable where
+
+class Representable f where
+  -- a
+  type Rep f :: *
+
+  -- alpha :: Reader a x -> F x
+  tabulate :: (Rep f -> x) -> f x
+
+  -- beta  :: F x -> Reader a x
+  index    :: f x -> Rep f -> x
+
+data Stream x = Cons x (Stream x)
+
+instance Functor Stream where
+  fmap f (Cons x xs) = Cons (f x) (fmap f xs)
+
+instance Representable Stream where
+  type Rep Stream = Int
+  tabulate f = Cons (f 0) (tabulate (f . (+1)))
+  index (Cons b bs) n | n == 0    = b
+                      | otherwise = index bs (n-1)  

2020/folivetti/day13/src/Main.hs

@@ -17,11 +17,17 @@ parseData dat = let (x:y:_) = lines dat
 sieve :: [(Integer, Integer)] -> Integer
 sieve = head . snd . foldl' go (1, [0])
   where
-    createSeeds mult x  = map (\i -> x + i*mult) [0..]
-    filterSeeds n a     = head . filter (\i -> (i+a) `mod` n == 0)
-    nextSeeds m n a     = createSeeds (m*n) . filterSeeds n a
+    createSeeds mult x  = map (\i -> x + i*mult) [0..] -- [x, x+mult..]
+    filterSeeds n a     = head . filter (\i -> (i+a) `mod` n == 0) 
+    nextSeeds m n a     = createSeeds (m*n) . filterSeeds n a -- map.filter 
 
-    go (m, seeds) (a,n) = (m*n, nextSeeds m n a seeds)
+    go (m, seeds) (a,n) = (m*n, nextSeeds m n a seeds) -- swap
+
+sieve' :: (Integer, Integer) -> (Integer, Integer) -> (Integer, Integer)
+sieve' (seed, mul) (offset, bus) = (smallestSolution, bus*mul)
+  where
+    smallestSolution = head [t | t <- [seed, seed+mul ..]
+                               , (t+offset) `rem` bus == 0]
 
 main :: IO ()
 main = do
@@ -32,3 +38,4 @@ main = do
       (tf, bus)      = minimumBy (comparing fst) $ zip turns buses
   print $ tf*bus
   print $ sieve offsBuses
+  print $ foldl' sieve' (0, 1) offsBuses

2020/folivetti/day14/LICENSE

@@ -0,0 +1,30 @@
+Copyright Author name here (c) 2020
+
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above
+      copyright notice, this list of conditions and the following
+      disclaimer in the documentation and/or other materials provided
+      with the distribution.
+
+    * Neither the name of Author name here nor the names of other
+      contributors may be used to endorse or promote products derived
+      from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

2020/folivetti/day14/README.md

@@ -0,0 +1 @@
+# day14

2020/folivetti/day14/Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

2020/folivetti/day14/day14.cabal

@@ -0,0 +1,20 @@
+name:                day14
+version:             0.1.0.0
+-- synopsis:
+-- description:
+homepage:            https://github.com/githubuser/day14#readme
+license:             BSD3
+license-file:        LICENSE
+author:              Author name here
+maintainer:          [email protected]
+copyright:           2020 Author name here
+category:            Web
+build-type:          Simple
+cabal-version:       >=1.10
+extra-source-files:  README.md
+
+executable day14
+  hs-source-dirs:      src
+  main-is:             Main.hs
+  default-language:    Haskell2010
+  build-depends:       base >= 4.7 && < 5, containers, split