'''lecture_17_copying_sublists.py
Explore issues involved in copying sublists
Oliver W. Layton
CS 151: Computational Thinking: Visual Media
Spring 2021
'''


# 1) Explore copying middle row then changing an item in the copy
digits = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
# middleRow = digits[1] # this is a list
# print(digits)
# print(middleRow)
# middleRow[0] = -99
# print(digits)
# print(middleRow)


# 2) Explore copying 1st two rows then modifying the copy
digits = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
# firstTwo = digits[:2]
# print(firstTwo)
# firstTwo[0][1] = -99
# print(firstTwo)
# print(digits)


# 3) Access single int, then change it
digits = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
# theFour = digits[1][0]  # int NOT an orginal sublist. So it is independent. (doesnt violate the rule)
# print(theFour)
# theFour = -99
# print(theFour)
# print(digits)


# 4) Access a list of basic types, but not one of the original sublists
# e.g. the 1st two ints in the first sublist
digits = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
slice = digits[1][:2]  # list of the 4 and 5
print(slice)
slice[0] = -99
print(slice)
print(digits)
print(slice)

# Full slice of sublist
# digits = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
# slice = digits[1][:]
# middleRow = digits[1] # list of the 4, 5, 6
# print('middle row:', middleRow)
# slice = middleRow[:]  # list of the 4, 5, 6
# print('full slice of middle row:', slice)
# slice[0] = -99
# print('middle row (after change):', middleRow)
# print('full slice of middle row (after change):', slice)

# 5) Access a list with a sublist of 3 turtle objects and another with 1 turtle object.
# Slice the 1st two ints in the first sublist
import turtle
myPets = [[turtle.Turtle(), turtle.Turtle(), turtle.Turtle()], [turtle.Turtle()]]
# myPets has 3 turtle objects in 1st sublist. 1 turtle in 2nd sublist.
print(myPets)

# Slice the 1st two Turtles in the first sublist
firstTwoTurts = myPets[0][:2]
print('First two turtles in 1st sublist:')
print(firstTwoTurts)

turt = firstTwoTurts[0]
# would change turtle 1st item in firstTwoTurts AND also 1st turtle in 1st sublist of myPets
turt.color('red')