Python 101 - Lesson 3 - Chapter 5

# Exercise 5.1
# Write a program which repeatedly
# reads numbers until the user enters “done”.
# Once “done” is entered, print out the total,
# count, and average of the numbers. If the user
# enters anything other than a number, detect
# their mistake using try and except and print
# an error message and skip to the next number.

total = 0
count = 0
average = 0

while count >= 0 :
  input_b = raw_input('Enter a number:')
  if input_b == 'done':
    print int(total), count, average
    break
  try:
    input = float(input_b)
    count = count + 1
    total = total + input
    average =  total / count
  except:
    print 'Invalid input'


# Exercise 5.2
# Write another program that prompts
# for a list of numbers as above and
# at the end prints out both the maximum
# and minimum of the numbers instead of the average.

number = None
numbers = []
count = 0
total = 0

maximum = None
minimum = None

while count >= 0 :
  number = raw_input('Enter a number:')
  if number == 'done':
    break
  try:
    number = int(number)
    count += 1
    numbers.append(number)
  except:
    print 'Invalid number'
    continue

for number in numbers:
  total += number
  if maximum is None or maximum < number:
    maximum = number
  if minimum is None or minimum > number:
    minimum = number

print count, total, maximum, minimum