Note: Don't forget to write the programs that allow the examiners to test the functions that you write.
Problem 1. Write a function
is_sorted_sum(L) that returns
True if the list
L of integers is sorted ascendingly by the sum of its elements' digits.
For example, the list $13, 11111, -17, 9, 1719$ is sorted as requested because the respective sums of digits are as follows:
|Sums of the digits||4||5||8||9||18|
Your function should not use the in-build
sorted commands: checking whether or not a list is sorted does not require any sorting.
Problem 2. Write a function
even_slice(L, a, b) that returns a new list containing all the even numbers among the elments of
L between indices
b (including both of them) in their original order. You may assume that
0 <= a <= b < len(L).
even_slice([11, 12, 2, 17, 20, 22, 2, 19, 7, 42, 18, 20], 2, 10)
should return the list of all the even numbers in the list
[2, 17, 20, 22, 2, 19, 7, 42, 18]. In other words, it should return
[2, 20, 22, 2, 42, 18]