#
# ps6pr4.py (Problem Set 6, Problem 4)
#
# TT Securities    
#
# Computer Science 111
#

def display_menu():
    """ prints a menu of options
    """  
    print()
    print('(0) Input a new list of prices')
    print('(1) Print the current prices')
    print('(2) Find the latest price')
    ## Add the new menu options here.

    print('(8) Quit')

def get_new_prices():
    """ gets a new list of prices from the user and returns it
    """
    new_price_list = eval(input('Enter a new list of prices: '))
    return new_price_list

def print_prices(prices):
    """ prints the current list of prices
        input: prices is a list of 1 or more numbers.
    """
    if len(prices) == 0:
        print('No prices have been entered.')
        return
    
    print('Day Price')
    print('--- -----')
    for i in range(len(prices)):
        print('%3d' % i, end='')
        print('%6.2f' % prices[i])

def latest_price(prices):
    """ returns the latest (i.e., last) price in a list of prices.
        input: prices is a list of 1 or more numbers.
    """
    return prices[-1]

## Add your functions for options 3-7 below.


def tts():
    """ the main user-interaction loop
    """
    prices = []

    while True:
        display_menu()
        choice = int(input('Enter your choice: '))
        print()

        if choice == 0:
            prices = get_new_prices()
        elif choice == 8:
            break
        elif choice < 8 and len(prices) == 0:
            print('You must enter some prices first.')
        elif choice == 1:
            print_prices(prices)
        elif choice == 2:
            latest = latest_price(prices)
            print('The latest price is', latest)
        ## add code to process the other choices here

            
        else:
            print('Invalid choice. Please try again.')

    print('See you yesterday!')