"""Lab10 starter code"""
from sets import *

# Q1
def is_subset(set1, set2):
    """Returns True if set2 is a subset of set1.

    >>> set1 = Rlist(1, Rlist(4, Rlist(2, Rlist(5))))
    >>> set2 = Rlist(1, Rlist(2, Rlist(4)))
    >>> is_subset(set1, set2)
    True
    >>> set3 = Rlist(1, Rlist(2, Rlist(3, Rlist(4))))
    >>> is_subset(set1, set3)
    False
    """

# Q2
def rlist_to_set(rlist):
    """Returns a set that contains unique elements in the given rlist.

    >>> r = Rlist(1, Rlist(2, Rlist(2, Rlist(1))))
    >>> rlist_to_set(r)
    Rlist(2, Rlist(1))
    """

# Q3
def rlist_to_set_mut(rlist):
    """Mutates the original Rlist by removing duplicate items.

    >>> r = Rlist(1, Rlist(2, Rlist(2, Rlist(1))))
    >>> rlist_to_set_mut(r)
    >>> r
    Rlist(2, Rlist(1))
    """

# Q5
def exclusive_or(set1, set2):
    """Returns a set containing elements in set1 or set2, but not
    elements that appear in both.

    >>> set1 = Rlist(1, Rlist(2, Rlist(3)))
    >>> set2 = Rlist(1, Rlist(3, Rlist(4)))
    >>> exclusive_or(set1, set2)
    Rlist(2, Rlist(4))
    """

# Q8
def max_set(s):
    """Finds the largest element in a set that is implemented as a 
    binary search tree.

    >>> s = Tree(4,
    ...            Tree(2,
    ...                   Tree(1)),
    ...            Tree(5,
    ...                   None,
    ...                   Tree(6)))
    >>> max_set(s)
    6
    """