Unique Characters in a string using a dictionary in Python: Write a Python program which asks the user for a string, and outputs number of unique characters in it. For example: 'Ethan' has 5 unique characters, 'Hello' has 4. Use a dictionary to achieve the functionality, not a set. Hint: Once a key is registered in a dictionary, you can assign values to it any number of times.
Unique Characters in a string using a dictionary in Python
enteredString = input("Please enter a string: ")
# Initialize the uniqueCharacters dictionary
uniqueCharacters = dict()
# Iterater over each character, and register it in the dictionary with any value. Any repeated occurence of a letter will reassign the given value to it, without creating a duplicate key.
for character in enteredString:
uniqueCharacters[character] = True
print("The entered string contains", len(uniqueCharacters), "unique character(s).")
Try it here.
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