Lecture Notes on 3 Jul 2013

Let num be an int.

* Write a boolean expression that evaluates to True if num is even.
num % 2 == 0

* Write a boolean expression that evaluates to True if num is a four
digit number that is divisible by 13.
(num >= 1000) and (num <= 9999) and (num % 13 == 0)

* Write a boolean expression that evaluates to True if num is not a
multiple of 12.
num % 12 != 0

* Write a boolean expression that evaluates to True if num is not
a three digit number and is not a factor of 120.
((num < 100) or (num > 999)) and (120 % num != 0)


# Computes the Pythagorean triples less than 100
def main():
  num_iter = 0
  num_triples = 0
  for c in range (100, 1, -1):
    for b in range (c - 1, 0, -1):
      for a in range (b, 0, -1):
        num_iter += 1
        if (a * a + b * b == c * c):
          num_triples += 1
          print (a, b, c)
  print ("Number of iterations = ", num_iter)
  print ("Number of triples = ", num_triples)
main()