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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).")
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