sets.py

#A set is an unordered collection of unique objects: 
a = {1, 2, 3}
b = {3, 4, 5}
b.add(6)
b.remove(6)

print(a)
print(b)

print(a.union(b)) #Python 3.X: (a | b)
print(a.intersection(b)) #Python 3.X: (a & b)
print(a.difference(b)) #Python 3.X: (a - b)
print(b.difference(a)) #Python 3.X: (b - a)
print(a.symmetric_difference(b)) #Python 3.X: (a ^ b)

# Union = {1, 2, 3, 4, 5}
# Intersection = {3}
# Difference of a - b = {1, 2}
# Difference of b - a = {4, 5}
# Symmetric difference = {1, 2, 4, 5}

Run Code

sets intro.py

moves = set()
moves.add("Barrel Roll")
moves.add("Zerg Rush")

print("Moves remaining:", moves)

if "Zerg Rush" in moves:
    print("Now doing a Zerg Rush!")
    moves.remove("Zerg Rush")

print("Moves remaining:", moves)

Run Code

1. Write a program that uses a set to add each of my guesses in a game of Battleships. If i have already guessed the co-ords, then the program should tell me:

   Guess: A3 
   Targeting A3 
   Guess: C4 
   Targeting C4 
   Guess: A3 
   You've chosen those co-ordinates already 
   Guess: B2 
   Targeting B2



2. ask your friend for 3 of their favourite foods. record this in a set. record your own favourite 3 foods too in another set. Use set theory to find patterns between your favourite foods and your friends favourite foods, e.g. what do you have in common? What do you like that your friend doesn't? etc.