Understanding - Advanced, exercise 27

Text

The variable my_mat_list contains the list of integers of a 10-digit matriculation number (e.g. [0, 0, 0, 0, 1, 2, 3, 4, 5, 6]), while the variable my_chars contains the set with all the alphabetic characters in lower case included in your full name (i.e. for the name John Doe we have the set {"j", "o", "n", "h", "d", "e"}). Study the execution of the following function when it is called as follows: c_rec(my_chars, my_mat_list).

def c_rec(chars, mat_list):
    result = ["a", "e", "i", "o", "u"]

    if len(mat_list) == 0:
        result = sorted(list(chars))
        return "".join(result)
    elif mat_list[0] % 2 == 0:
        idx = mat_list[0] % len(result)
        chars.add(result[idx])

    return c_rec(chars, mat_list[1:])

Hints

The function c_rec is a recursive function that works until all the numbers in the input list are considered.

Additional material

The runnable Python file is available online. You can run it executing the command python exercise_27.py in a shell, and then following the instructions on screen to specify the intended input.