From afae39a832fbdf0f5bf67e20cac7bdf224b0a290 Mon Sep 17 00:00:00 2001 From: Determinant Date: Sun, 28 May 2017 18:19:31 -0400 Subject: init --- 1-10/1.hs | 3 +++ 1-10/10.hs | 9 +++++++++ 1-10/2.hs | 4 ++++ 1-10/3.hs | 5 +++++ 1-10/4.hs | 2 ++ 1-10/5.hs | 4 ++++ 1-10/6.hs | 3 +++ 1-10/7.hs | 4 ++++ 1-10/8.hs | 4 ++++ 1-10/9.hs | 5 +++++ 1-10/t.hs | 2 ++ 11 files changed, 45 insertions(+) create mode 100644 1-10/1.hs create mode 100644 1-10/10.hs create mode 100644 1-10/2.hs create mode 100644 1-10/3.hs create mode 100644 1-10/4.hs create mode 100644 1-10/5.hs create mode 100644 1-10/6.hs create mode 100644 1-10/7.hs create mode 100644 1-10/8.hs create mode 100644 1-10/9.hs create mode 100644 1-10/t.hs diff --git a/1-10/1.hs b/1-10/1.hs new file mode 100644 index 0000000..0d2f07a --- /dev/null +++ b/1-10/1.hs @@ -0,0 +1,3 @@ +myLast [] = error "empty list" +myLast [x] = x +myLast (_:xs) = myLast xs diff --git a/1-10/10.hs b/1-10/10.hs new file mode 100644 index 0000000..0cc6a9a --- /dev/null +++ b/1-10/10.hs @@ -0,0 +1,9 @@ +pack :: Eq a => [a] -> [[a]] + +pack [] = [] +pack [x] = [[x]] +pack (x:xs) = if x == head y then (x:y):ys else [x]:(y:ys) where (y:ys) = pack xs + +encode :: Eq a => [a] -> [(Int, a)] + +encode xs = map (\x -> (length x, head x)) $ pack xs diff --git a/1-10/2.hs b/1-10/2.hs new file mode 100644 index 0000000..baeb995 --- /dev/null +++ b/1-10/2.hs @@ -0,0 +1,4 @@ +myButLast [] = error "empty list" +myButLast [x] = error "list with single element" +myButLast (x:[y]) = x +myButLast (x:xs) = myButLast xs diff --git a/1-10/3.hs b/1-10/3.hs new file mode 100644 index 0000000..660ae64 --- /dev/null +++ b/1-10/3.hs @@ -0,0 +1,5 @@ +elementAt [] _ = error "out of range" +elementAt (x:_) 1 = x +elementAt (_:xs) k + | k < 1 = error "out of range" -- deal with the infinite list + | otherwise = elementAt xs (k - 1) diff --git a/1-10/4.hs b/1-10/4.hs new file mode 100644 index 0000000..28c1423 --- /dev/null +++ b/1-10/4.hs @@ -0,0 +1,2 @@ +myLength [] = 0 +myLength (_:xs) = 1 + myLength xs diff --git a/1-10/5.hs b/1-10/5.hs new file mode 100644 index 0000000..b18724c --- /dev/null +++ b/1-10/5.hs @@ -0,0 +1,4 @@ +myReverse l = f l [] + where + f [] b = b + f (x:xs) b = f xs (x:b) diff --git a/1-10/6.hs b/1-10/6.hs new file mode 100644 index 0000000..24f4d8c --- /dev/null +++ b/1-10/6.hs @@ -0,0 +1,3 @@ +import Data.List +isPalindrome :: Eq a => [a] -> Bool +isPalindrome l = foldl' (\flag (a, b) -> flag && a == b) True (zip l (reverse l)) diff --git a/1-10/7.hs b/1-10/7.hs new file mode 100644 index 0000000..0ebd030 --- /dev/null +++ b/1-10/7.hs @@ -0,0 +1,4 @@ +data NestedList a = Elem a | List [NestedList a] + +flatten (Elem x) = [x] +flatten (List xs) = concat $ map flatten xs diff --git a/1-10/8.hs b/1-10/8.hs new file mode 100644 index 0000000..01d1781 --- /dev/null +++ b/1-10/8.hs @@ -0,0 +1,4 @@ +compress :: Eq a => [a] -> [a] +compress (x:y:xs) = if x == y then compress(y:xs) else x:compress(y:xs) +compress [] = [] +compress [x] = [x] diff --git a/1-10/9.hs b/1-10/9.hs new file mode 100644 index 0000000..e9630f4 --- /dev/null +++ b/1-10/9.hs @@ -0,0 +1,5 @@ +pack :: Eq a => [a] -> [[a]] + +pack [] = [] +pack [x] = [[x]] +pack (x:xs) = if x == head y then (x:y):ys else [x]:(y:ys) where (y:ys) = pack xs diff --git a/1-10/t.hs b/1-10/t.hs new file mode 100644 index 0000000..6a4448d --- /dev/null +++ b/1-10/t.hs @@ -0,0 +1,2 @@ +grp [] = [] +grp (x:xs) = (x:(filter (==x) xs)):(grp $ filter (/=x) xs) -- cgit v1.2.3