Design a function my-doubles that takes a list of numbers and returns a new list
where each element is twice what the corresponding element was in the original list.
Re-implement the same function as my-doubles-map using map from the
lists library. Which implementation do you find clearer?
Design my-string-lens, which takes a list of strings and returns a new
list where each element is the length of the string in the corresponding
position in the input list.
Re-implement the same function as my-string-lens-map using map from the
lists libray. Which implementation do you find clearer?
Design my-pos-nums, which takes a list of numbers and returns a new list
that contains only those numbers in the original list that are positive.
Re-implement the same function as my-pos-nums-filter using filter from the
lists library. Which implementation do you find clearer?
Design my-alternating, which takes a list of any element and returns a new
list that contains every other element -- i.e., keep the first, skip the
second, etc. Note: you may need two mutable variables for this one -- one to
contain the result, as normal, but the other to keep track of the alternation.
Can you express my-alternating using either map or filter?
Design my-running-sum, that takes a list of numbers and returns a list where
each position conta a sum of the numbers in the original list up the
corresponding position. i.e., my-running-sum([list: 1, 2, 3]) is [list: 1, 3, 6].
Can you express my-running-sum using either map or filter?