Python: Select a string from a given list of strings with the most unique characters

Python Programming Puzzles: Exercise-28 with Solution

Write a Python program to select a string from a given list of strings with the most unique characters.

Input:
['cat', 'catatatatctsa', 'abcdefhijklmnop', '124259239185125', '', 'foo', 'unique']
Output:
abcdefhijklmnop

Input:
['Green', 'Red', 'Orange', 'Yellow', '', 'White']
Output:
Orange

Pictorial Presentation:

Sample Solution-1:

Python Code:

#License: https://bit.ly/3oLErEI
def test(strs):
    return max(strs, key=lambda x: len(set(x)))
strs = ['cat', 'catatatatctsa', 'abcdefhijklmnop', '124259239185125', '', 'foo', 'unique']
print("Original list:")
print(strs)
print("Select a string from the said list of strings with the most unique characters:")
print(test(strs))
strs = ['Green', 'Red', 'Orange', 'Yellow', '', 'White']
print("\nOriginal list:")
print(strs)
print("Select a string from the said list of strings with the most unique characters:")
print(test(strs))

Sample Output:

Original list:
['cat', 'catatatatctsa', 'abcdefhijklmnop', '124259239185125', '', 'foo', 'unique']
Select a string from the said list of strings with the most unique characters:
abcdefhijklmnop

Original list:
['Green', 'Red', 'Orange', 'Yellow', '', 'White']
Select a string from the said list of strings with the most unique characters:
Orange

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Sample Solution-2:

Python Code:

#License: https://bit.ly/3oLErEI

def test(strs):
    largest_set = {}
    n = 0
    largest = None
    for phrase in strs:
        diff = len(largest_set) - len(set(phrase))
        if diff < 0:
            largest_set = set(phrase)
            largest = phrase
            n = len(largest_set)
        elif diff == 0:
            if n < len(set(phrase)):
                largest_set = set(phrase)
                largest = phrase
                n = len(largest_set)
        else:
            pass
    return largest
strs = ['cat', 'catatatatctsa', 'abcdefhijklmnop', '124259239185125', '', 'foo', 'unique']
print("Original list:")
print(strs)
print("Select a string from the said list of strings with the most unique characters:")
print(test(strs))
strs = ['Green', 'Red', 'Orange', 'Yellow', '', 'White']
print("\nOriginal list:")
print(strs)
print("Select a string from the said list of strings with the most unique characters:")
print(test(strs))

Sample Output:

Original list:
['cat', 'catatatatctsa', 'abcdefhijklmnop', '124259239185125', '', 'foo', 'unique']
Select a string from the said list of strings with the most unique characters:
abcdefhijklmnop

Original list:
['Green', 'Red', 'Orange', 'Yellow', '', 'White']
Select a string from the said list of strings with the most unique characters:
Orange

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor :

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