2020-10 in haskell

6 files changed, 227 insertions, 0 deletions

diff --git a/2020/10-Adapter_Array/#second.hs# b/2020/10-Adapter_Array/#second.hs#
new file mode 100644
index 0000000..8e581a0
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+++ b/2020/10-Adapter_Array/#second.hs#
@@ -0,0 +1,36 @@
+module Main (main) where
+import Control.Monad (when)
+import Data.List (group, sort)
+import System.Exit (die)
+
+exampleExpectedOutput = 8
+exampleExpectedOutput2 = 19208
+
+parseInput :: String -> IO [Int]
+parseInput filename = do
+  input <- readFile filename
+  return $ map read $ lines input
+
+compute :: [Int] -> Int
+compute jolts = product $ map (([1, 1, 2, 4, 7, 13, 24] !!) . length) $ filter ((==) 1 . head) $  group $ zipWith (-) s (0 : s) --snd . head $ foldl compute' [(0, 1)] $ sort jolts
+  where
+    s = sort jolts
+    --compute' (prev, n) x =
+    --compute' (x:xs) = (length $ takeWhile (\i -> i <= x + 3) xs) * compute' xs
+
+main :: IO ()
+main = do
+  example <- parseInput "example"
+  let s = sort example
+  print s
+  print $ zipWith (-) s (0 : s)
+  print $ group $ zipWith (-) s (0 : s)
+  print $ filter ((==) 1 . head) $ group $ zipWith (-) s (0 : s)
+  print $ map length $ filter ((==) 1 . head) $ group $ zipWith (-) s (0 : s)
+  let exampleOutput = compute example
+  when  (exampleOutput /= exampleExpectedOutput)  (die $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
+  example2 <- parseInput "example2"
+  let exampleOutput2 = compute example2
+  when  (exampleOutput2 /= exampleExpectedOutput2)  (die $ "example2 failed: got " ++ show exampleOutput2 ++ " instead of " ++ show exampleExpectedOutput2)
+  input <- parseInput "input"
+  print $ compute input
diff --git a/2020/10-Adapter_Array/example b/2020/10-Adapter_Array/example
new file mode 100644
index 0000000..ec4a03f
--- /dev/null
+++ b/2020/10-Adapter_Array/example
@@ -0,0 +1,11 @@
+16
+10
+15
+5
+1
+11
+7
+19
+6
+12
+4
diff --git a/2020/10-Adapter_Array/example2 b/2020/10-Adapter_Array/example2
new file mode 100644
index 0000000..e6376dc
--- /dev/null
+++ b/2020/10-Adapter_Array/example2
@@ -0,0 +1,31 @@
+28
+33
+18
+42
+31
+14
+46
+20
+48
+47
+24
+23
+49
+45
+19
+38
+39
+11
+1
+32
+25
+35
+8
+17
+7
+9
+4
+2
+34
+10
+3
diff --git a/2020/10-Adapter_Array/first.hs b/2020/10-Adapter_Array/first.hs
new file mode 100644
index 0000000..0157a3b
--- /dev/null
+++ b/2020/10-Adapter_Array/first.hs
@@ -0,0 +1,31 @@
+module Main (main) where
+import Control.Monad (when)
+import Data.List (foldl', sort)
+import System.Exit (die)
+
+exampleExpectedOutput = 35
+exampleExpectedOutput2 = 220
+
+parseInput :: String -> IO [Int]
+parseInput filename = do
+  input <- readFile filename
+  return $ map read $ lines input
+
+compute :: [Int] -> Int
+compute jolts = result $ foldl' compute' (0, 0, 0) $ sort jolts
+  where
+    compute' (prev, ones, threes) jolt
+      | jolt - prev == 1 = (jolt, ones + 1, threes)
+      | jolt - prev == 3 = (jolt, ones, threes + 1)
+    result (_, ones, threes) = ones * (threes + 1)
+
+main :: IO ()
+main = do
+  example <- parseInput "example"
+  let exampleOutput = compute example
+  when  (exampleOutput /= exampleExpectedOutput)  (die $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
+  example2 <- parseInput "example2"
+  let exampleOutput2 = compute example2
+  when  (exampleOutput2 /= exampleExpectedOutput2)  (die $ "example2 failed: got " ++ show exampleOutput2 ++ " instead of " ++ show exampleExpectedOutput2)
+  input <- parseInput "input"
+  print $ compute input
diff --git a/2020/10-Adapter_Array/input b/2020/10-Adapter_Array/input
new file mode 100644
index 0000000..2ef0266
--- /dev/null
+++ b/2020/10-Adapter_Array/input
@@ -0,0 +1,89 @@
+67
+118
+90
+41
+105
+24
+137
+129
+124
+15
+59
+91
+94
+60
+108
+63
+112
+48
+62
+125
+68
+126
+131
+4
+1
+44
+77
+115
+75
+89
+7
+3
+82
+28
+97
+130
+104
+54
+40
+80
+76
+19
+136
+31
+98
+110
+133
+84
+2
+51
+18
+70
+12
+120
+47
+66
+27
+39
+109
+61
+34
+121
+38
+96
+30
+83
+69
+13
+81
+37
+119
+55
+20
+87
+95
+29
+88
+111
+45
+46
+14
+11
+8
+74
+101
+73
+56
+132
+23
diff --git a/2020/10-Adapter_Array/second.hs b/2020/10-Adapter_Array/second.hs
new file mode 100644
index 0000000..cb99e9a
--- /dev/null
+++ b/2020/10-Adapter_Array/second.hs
@@ -0,0 +1,29 @@
+module Main (main) where
+import Control.Monad (when)
+import Data.List (group, sort)
+import System.Exit (die)
+
+exampleExpectedOutput = 8
+exampleExpectedOutput2 = 19208
+
+parseInput :: String -> IO [Int]
+parseInput filename = do
+  input <- readFile filename
+  return $ map read $ lines input
+
+compute :: [Int] -> Int
+compute jolts = product $ map (([0, 1, 2, 4, 7] !!) . length) $ filter ((==) 1 . head) $  group $ zipWith (-) s (0 : s)
+  where
+    s = sort jolts
+
+main :: IO ()
+main = do
+  example <- parseInput "example"
+  let s = sort example
+  let exampleOutput = compute example
+  when  (exampleOutput /= exampleExpectedOutput)  (die $ "example failed: got " ++ show exampleOutput ++ " instead of " ++ show exampleExpectedOutput)
+  example2 <- parseInput "example2"
+  let exampleOutput2 = compute example2
+  when  (exampleOutput2 /= exampleExpectedOutput2)  (die $ "example2 failed: got " ++ show exampleOutput2 ++ " instead of " ++ show exampleExpectedOutput2)
+  input <- parseInput "input"
+  print $ compute input