Counts letters

def count_characters(input_string):
    upper_count = 0
    lower_count = 0
    digit_count = 0
    space_count = 0

    for char in input_string:
        if char.isupper():
            upper_count += 1
        elif char.islower():
            lower_count += 1
        elif char.isdigit():
            digit_count += 1
        elif char.isspace():
            space_count += 1

    return upper_count, lower_count, digit_count, space_count

def main():
    user_input = input("Enter a string: ")
    upper, lower, digits, spaces = count_characters(user_input)

    print(f"Uppercase letters: {upper}")
    print(f"Lowercase letters: {lower}")
    print(f"Digits: {digits}")
    print(f"Spaces: {spaces}")

if __name__ == "__main__":
    main()