"""
Programming Techniques — Lecture 5
Guided exercise solution: conditional statements and input validation
"""

FULL_PRICE = 12.00
REDUCED_PRICE = 7.00
MIN_AGE = 0
MAX_AGE = 120
REDUCED_LIMIT = 18

age_text = input("Enter your age: ")

if age_text.isdigit():
    age = int(age_text)

    if age < MIN_AGE or age > MAX_AGE:
        print("Invalid age: value outside the accepted range.")
    elif age < REDUCED_LIMIT:
        price = REDUCED_PRICE
        print(f"Reduced ticket: €{price:.2f}")
    else:
        price = FULL_PRICE
        print(f"Full-price ticket: €{price:.2f}")
else:
    print("Invalid input: please enter age using digits only.")