Batch 2 - Class 36 - Mad Vet, Flowcharts

• Program the state diagram you did in class (Combination Lock or Elevator)
• Another Mad Vet has these three machines: Machine #1 turns one cat into one dog. Machine #2 turns one dog into one cat, one dog, and one mouse Machine #3 turns one mouse into one cat and one dog. This Mad Vet has one cat. 

  Can she convert it into three cats and one dog? Answer: Yes (1, 2, 3, -1)Can she convert it into two cats?Answer: No - Invariant is (C+D+2M) mod 3

  Instructor Notes: Help kids find simple relationships such as C=D, M=2D and M=2C, 2M=D and 2M=C, D=4C and D=4D and C=4D and C=4C - then try to piece these together

  
  

  Can she convert it into three cats?Answer: No - Same as aboveCan she convert it into one mouse?Answer: No - Same as above The Mad Vet is looking to close down the business, but she’d like to finish his Mad Vet business owning only one mouse (and no other animals). From your answer to Question above, you know she can’t simply use the cat she has to produce one mouse. So she’ll go to the pet shop down the street and buy some animals, and then use those animals together with her one cat to produce a mouse. What animals should she buy at the pet shop? Answer: One more dogUsing these three Mad Vet machines, how many different "classes" of animals are there? Describe all of the classes. Answer: 3A friend of this Mad Vet brings her, as a birthday present, a cat and a mouse. But our Mad Vet prefers to have just one cat. Can she transmogrify her new collection of animals back to the way things were when she only had one cat? Answer: Yes - Identity notionDoes you answer to the previous question depend on the fact that our Mad Vet started with one cat? That is, if she started with ANY collection of animals, and her friend brought her a cat and a mouse, would she be able to transmogrify her collection back to the original collection? Answer: Yes - Identity notionBy adding animals from the pet shop to the cat she currently owns, is it possible for the Mad Vet to finish her Mad Vet business owning whatever collection of animals she’d like? Answer: YesDoes your answer to Question 9 above depend on the fact that she happens to currently own one cat? Answer: Yes

• Our final Mad Vet has these three machines: Machine #1 turns one cat into one dog Machine #2 turns one dog into one cat and one mouse Machine #3 turns one mouse into two mice This Mad Vet has one cat. 

• Can he convert it into two cats? Three cats? Any number of cats?
• Can he convert it into one mouse? 
• Using these three Mad Vet machines, how many different "classes" of animals are there? Describe all of the classes. 
• Is there some collection of animals this Mad Vet should ask to get as a gift from a friend so that he will still be able to have just one cat? 
• Does your answer to the previous question depend on the fact that the Mad Vet starts with one cat? 
• The Mad Vet is looking to close down the business, but he’d like to finish his Mad Vet business owning only one mouse (and no other animals). From your answer to a previous question, you know he can’t simply use the cat he has to produce one mouse. So he’ll go to the pet shop down the street and buy some animals, and then use those animals together with his one cat to produce a mouse. What animals should he buy at the pet shop? 
• By adding animals from the pet shop to the cat she currently owns, is it possible for the Mad Vet to finish her Mad Vet business owning whatever collection of animals 7she’d like? 
• Does your answer to Question 3.6 depend on the fact that she happens to currently own one cat? 

• Introduce the basic symbols of flowcharts - start/end, process, decision, input/output
• Draw a simple flowchart to illustrate - check mail in mailbox
• Reading flowcharts exercises
• Debugging flowcharts exercises
• Build your own flowchart - ask kids to pick up a problem/game and construct a flowchart
• Relationship between flowchart and state diagram

  State diagrams can be embedded within flowcharts (Eg: Elevator)State diagrams describe what the system does; Flowchart describes the exact processTo establish the difference, draw a flowchart that runs any state diagram stored in a table

• Program the flowchart that you built