How to find the longest word of 3 strings

Question

Hi everyone,

I am trying to return the longest word of these three strings. If the strings are the same in length it needs to return both of the words if possible.

def longest (s1, s2, s3):

    return max(len(s1, s2, s3))

print (longest ('hello', 'treehouse', 'code')) # should return 'elegant'
print (longest ('code', 'hello', 'treehouse')) # should return 'elegant'
print (longest ('treehouse', 'code', 'hello')) # should return 'elegant'

print (longest ('same', 'same', 'length')) # should return 'elegant'

I believe that you cannot use more then one argument for len()

Thanks for the help.

Answer 1 · 2016-09-19T23:36:00Z

September 19, 2016 11:36pm

Hi John,

You can pass multiple arguments to the max() function.

Probably the closest to what you tried to do would be

def longest (s1, s2, s3):
    return max(s1, s2, s3, key=len)

That's saying to return the maximum of the first 3 arguments using the len() function to decide the maximum value. It will only return the first occurrence if there's more than 1 maximal value.

If you want to return all words that have the maximum length then you could get the maximum length and then use a list comprehension to generate a list with all the words that have that maximum length.

def longest (s1, s2, s3):
    max_length = len(max(s1, s2, s3, key=len)) # get the maximum word and then the length of that word
    return [word for word in [s1, s2, s3] if len(word) == max_length]

In the list comprehension, it's iterating over each word in the list of 3 words. If the length of that word equals the max_length then it will be included in the output list.

If you're not familiar with list comprehensions there's a workshop on them that Kenneth did.

https://teamtreehouse.com/library/python-comprehensions

Answer 2 · 2016-09-19T04:10:47Z

September 19, 2016 4:10am

def longest (s1, s2, s3):
    # Transform in a list
    word_list = s1 + "," + s2 + "," + s3
    word_list = word_list.split(",")

    longest = len(max(word_list,key=len))

    for word in word_list:
        if len(word) == longest:
            print(word)


longest('hello', 'treehouse', 'codex')
print("-"*30)
longest('holla', 'hello', 'ks')

I do this, it works lol

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John Michael

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How to find the longest word of 3 strings

2 Answers

Jason Anello

Jason Anello

John Michael

John Michael

Arthur Kay

Arthur Kay