Sum of a list when boundry is given

sigma::Int->Int->Int
sigma x y = foldr(+) 0 (map (^2) [x..y])

Reverse a list using recursion and inbuilt libraries

reversep::[a]->[a]

reversep []=[]

reversep( x:xs) = reverse xs ++ [x]

Reverse a List

rev::[Int]->[Int]

rev (x:xs) = reverse (x:xs)

Factorial using recursion

fact::Int->Int

fact 0 =1

fact x | x >0 = x * fact (x-1)

Length of a list using length function

--Q4

lgn::[Int]->Int

lgn [] =0

lgn xs = length xs

nth Element of a List

kElem::[Int]->Int->Int

kElem (x:xs) n = xs !! n-x

Last Element -1 of a List

nElm::[Int]->Int

nElm [x]=x

nElm (x:xs) = reverse xs !! 1