'''lecture_21_while_miles.py
Use a while loop to get mileage from trips. Loop sentinel is a negative milage (invalid entry)
Goal: Compute the total number of miles across all trips and average trip miles
UPDATE 1: Add break statement if sentinel is negative
UPDATE 2: Introduce increment operator
Oliver W. Layton
CS 151: Computational Thinking: Visual Media
Fall 2020
'''
# Declare variables for number of trips that are entered and total miles entered

# Get user input

# Get data while the user entry is valid (>0), first updating the mileage total and number of trips

# Compute the average number of miles across all trips

# Print number of total miles and total numebr of trips

# Print number of average number of miles