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David Sands An English (or EnglishSwedish, or EnglishX) dictionary
Completing Part I gives a 3 or a G; 
Part I (7 small assignments)

Part II (2 larger assignments)

Please read the following guidelines carefully: 
Part I
You have to complete 5 out of the following 7 assignments to get a pass on the exam.
Given the following function
q2 :: Eq a => [a] > [a]
q2 [] = []
q2 (x:xs)  x `elem` xs = q2 [y  y < xs, y /= x]
 otherwise = x : q2 xs
what would the following expression give in ghci?
q2 ( words "spam eggs chips spam")
In this question you should assume that you have a function rainfall
which computes the rainfall in Gothenburg for a given week (where weeks are numbered from 1 and upwards)
type WeekNumber = Int
rainfall :: WeekNumber > Double  assume this function exists
Complete the definition of the following function:
mostRain :: WeekNumber > Double
mostRain n  n < 1 = 0
 otherwise =  (complete this case)
such that mostRain n
(when n > 0
) gives the amount of rain in the rainiest week from week 1 up to and including week n
.
For example, suppose that the rainfall in week 3 is 20.5 (rainfall 3 == 20.5
). Now if week number 3 is the rainiest of the first 50 weeks, then mostRain 50 == 20.5
.
Your solution must be recursive. Solutions that do not use recursion will be considered incorrect.
Hint: The function max
may be useful. Note that you do not have to provide a definition for the function rainfall
.
The following datatypes are used to represent a hand of cards:
data Suit = Hearts  Clubs  Diamonds  Spades
deriving Eq
data Rank = Numeric Int  Jack  Queen  King  Ace
deriving Eq
data Card = NormalCard Rank Suit  Joker  different from lab 2
deriving Eq
Define a function
countAces:: [Card] > Int
where countAces
returns the number of cards in the given hand which are either aces or jokers. So for example, if there are three aces and two jokers in the hand, the answer will be five.
Given the following data type for arithmetic expressions:
data Expr = Num Double  BinOp Op Expr Expr
deriving (Eq,Show)
data Op = Add  Mul
deriving (Eq,Show)
Define a function
countOp :: Op > Expr > Int
which counts the number of occurrences of a given operator in an expression. For example, the expression representing 1 + 2 + 3 * 4
is
example = BinOp Add (Num 1)
(BinOp Add (Num 2)
(BinOp Mul (Num 3)
(Num 4)
)
)
and countOp Add example
would give 2
.
Write a QuickCheck property prop_map_filter
that relates a list comprehension of the form:
[f x  x < xs, p x]
with functions map
and filter
.
Consider these two similar functions which modify every other element of their list argument:
bf,df :: [Int] > [Int]
bf [] = []
bf [x] = [abs x]
bf (x:y:xs) = (abs x) : y : bf xs
df [] = []
df [x] = [x + 1]
df (x:y:xs) = (x + 1) : y : df xs
Define a more general function gf :: (a > a) > [a] > [a]
such that the following property holds:
prop_gf xs = bf xs == gf abs xs
&& df xs == gf (+1) xs
Give the definition of a quickCheck generator
luckyList :: Gen [Integer]
for lists of Integers, where every list generated contains at least one 7
. Hint: generate two lists of numbers and use those to build one list guaranteed to contain the number 7.
Part II
You do not need to work on this part if you only want to get a 3 or a G (although a correct answer to part II can be used instead of a question in part I).
If you want to get a 4 you have to pass part I and one of the following assignments.
If you want to get a 5 or a VG, you have to do Part I, plus both of the following assignments.
11.
Question omitted (see old exams for examples)