Python Question:

Design and implement encoder and decoder functions that perform run length compression of strings (https://en.wikipedia.org/wiki/Run-length_encoding).

a. Run length string encoder: The encoder function should take a string as a parameter, and return the encoded string, represented in a list.

For example:

Given the string: aadccccaa

The encoded string will be: [[a, 2], [d, 1], [c, 4], [a, 2]].

b. Run length string decoder: The decoder function should take an encoded string (represented in a list) as a parameter, and return the original string.

For example:

Given the encoded string: [[a, 2], [d, 1], [c, 4], [a, 2]]

The decoded string is: aadccccaa.

Note: Use the top down design approach to break the problem into smaller sub-problems that can be used to solve it.