diff --git a/Assets/Solutions/Mid-Term/Missed-Mid-Term.md b/Assets/Solutions/Mid-Term/Missed-Mid-Term.md index 038992a..31d288b 100644 --- a/Assets/Solutions/Mid-Term/Missed-Mid-Term.md +++ b/Assets/Solutions/Mid-Term/Missed-Mid-Term.md @@ -5,19 +5,19 @@ ## Missed Mid-Term Question Paper with Solutions ![](https://img.shields.io/badge/Missed_MidTerm_Exam-8th_May-orange) -#### 1. Write the \textit{type signature} of the below functions. +#### 1. Write the _type signature_ of the below functions. (a) **drop:: Int -> [a] -> [a]** <br/> (b) **map:: (a->b) -> [a] -> [b]** <br/> (c) **concat:: [[a]] -> [a]** <br/> #### 2. Write a function _pairwiseConcat_ in Haskell that takes two lists of strings and concatenates them pairwise. -If one list is longer than the other, the extra elements should be ignored. -Usage Example: - 1. \> _pairwiseConcat_ [”a”, ”b”, ”c”] [”x”, ”y”, ”z”] +If one list is longer than the other, the extra elements should be ignored. <br/> +_Usage Example:_ + 1. \> _pairwiseConcat_ [”a”, ”b”, ”c”] [”x”, ”y”, ”z”] <br/> [”ax”, ”by”, ”cz”] - 2. \> _pairwiseConcat_ [”hello”, ”world”] [”!”, ”?”, ”!!”] + 2. \> _pairwiseConcat_ [”hello”, ”world”] [”!”, ”?”, ”!!”] <br/> ["hello!", "world?"] - 3. \> pairwiseConcat [] [”a”, ”b”, ”c”] + 3. \> pairwiseConcat [] [”a”, ”b”, ”c”] <br/> [] **Solution:** @@ -71,6 +71,26 @@ putStrLn $ "Is 89 in the tree? " ++ show (search 89 examTree) putStrLn $ "Is 90 in the tree? " ++ show (search 90 examTree) ``` +**Tracing:** +- foldr insert EmptyTree [78, 14, 03, 89] + - **insert 89 EmptyTree** + - (Node 89 EmptyTree EmptyTree) + - **insert 03 (Node 89 EmptyTree EmptyTree)** + - 03 < 89 = True + - Node 89 (insert 03 EmptyTree) EmptyTree + - (Node 89 (Node 03 EmptyTree EmptyTree) EmptyTree) + - **insert 14 (Node 89 (Node 03 EmptyTree EmptyTree) EmptyTree)** + - 14 < 89 = True + - Node 89 (insert 14 (Node 03 EmptyTree EmptyTree)) EmptyTree + - 14 > 03 = True + - Node 03 EmptyTree (insert 14 EmptyTree) + - Node 03 EmptyTree (Node 14 EmptyTree EmptyTree) + - (Node 89 (Node 03 EmptyTree (Node 14 EmptyTree EmptyTree)) EmptyTree) + - **insert 78 (Node 89 (Node 03 EmptyTree (Node 14 EmptyTree EmptyTree)) EmptyTree)** + - 78 < 89 = True + - complete it.... + - **Node 89 (Node 3 EmptyTree (Node 14 EmptyTree (Node 78 EmptyTree EmptyTree))) EmptyTree** + #### 7. Identify the key characteristic of Haskell that underscores its focus on composing functions and data structures to create concise and expressive code **Solution:** Higher-order functions @@ -89,7 +109,9 @@ correctly calculate the sum of all positive elements in the given list ’xs’. ``` sumPositive :: [Int] -> Int sumPositive [] = 0 -sumPositive (x:xs) = x + sumPositive xs +sumPositive (x:xs) + | x > 0 = x + sumPositive xs + | otherwise = sumPositive xs ``` #### 9. Given the following _data_ type declaration, What does the function getValue return when provided with 6 as input?