“Who Likes It” Code Challenge in Python

The Challenge

You probably know the “like” system from Facebook and other pages. People can “like” blog posts, pictures or other items. We want to create the text that should be displayed next to such an item.

Implement a function likes :: [String] -> String, which must take in input array, containing the names of people who like an item. It must return the display text as shown in the examples:

likes [] // must be "no one likes this"
likes ["Peter"] // must be "Peter likes this"
likes ["Jacob", "Alex"] // must be "Jacob and Alex like this"
likes ["Max", "John", "Mark"] // must be "Max, John and Mark like this"
likes ["Alex", "Jacob", "Mark", "Max"] // must be "Alex, Jacob and 2 others like this"

For 4 or more names, the number in and 2 others simply increases.

Test cases

Test.assert_equals(likes([]), 'no one likes this')
Test.assert_equals(likes(['Peter']), 'Peter likes this')
Test.assert_equals(likes(['Jacob', 'Alex']), 'Jacob and Alex like this')
Test.assert_equals(likes(['Max', 'John', 'Mark']), 'Max, John and Mark like this')
Test.assert_equals(likes(['Alex', 'Jacob', 'Mark', 'Max']), 'Alex, Jacob and 2 others like this')

The solution in Python

def likes(names):
    # get the total names
    n = len(names)
    
    # if none
    if n==0:
        return 'no one likes this'
    # if one
    elif n==1:
        return f"{names[0]} likes this"
    # if two
    elif n==2:
        return f"{names[0]} and {names[1]} like this"
    # if three
    elif n==3:
        return  f"{names[0]}, {names[1]} and {names[2]} like this"
    # if more than three
    else:
        return f"{names[0]}, {names[1]} and {n-2} others like this"