finding longest word in a list python

Question

I am trying to find the longest word in a non-empty list. My function is supposed to return the longest word. If elements are of equal length in the list, I am trying to sort out the longest in terms of Unicode sorting. For example, I am trying to return the following:

    >>> highest_word(['a', 'cat', 'sat'])
    'sat'
    >>> highest_word(['saturation', 'of', 'colour'])
    'saturation'
    >>> highest_word(['samIam'])
    'samIam'

So far I can get the first one to work, this is my code so far:

    def highest_word(wordlist):
    longestWord = ""
    max_len = 0

    for word in wordlist:

        if len(word) > max_len:
            longestWord = len(word)
            longestWord = word
    return longestWord

Any sort of help would be greatly appreciated.

Answer 1

Here's a simple one liner

print(max(['a', 'cat', 'sat', 'g'], key=lambda s: (len(s), s)))

This works by mapping each element of the list to a tuple containing its length and the string itself.

When comparing two tuples A and B , if A[0] > B[0] then A > B . Only if A[0] == B[0] are the second elements considered. So if the lengths of two strings are equal, then the strings are compared as a tiebreaker.