# sets -- some operations and examples
#
# Matt Bishop, MHI 289I, Winter 2019
#
# create the sets
a = [ 1, 2, 3, 4, 5, 5 ]
b = [ 4, 5, 6, 6, 7, 8 ]
c = [ 7, 7, 8, 9, 10, 11]

# build the sets from the lists
sa = set(a)
sb = set(b)
sc = set(c)

# show the two
print("List a:", a, " set sa:", sa)
print("List b:", b, " set sb:", sb)
print("List c:", c, " set sc:", sc)

# pause
input("\nHit return to continue"); print("\n", end='')

# now a set from a word
s = "supercalifragilisticexpealadocious"
ls = list(s)
ss = set(ls)

# show them
print("String:", s, "\nList:", ls, "\nset:", ss)

# pause
input("\nHit return to continue"); print("\n", end='')

# print the size of our sets
print("Length of list a:", len(list(a)), "and size of set sa:", len(sa))
print("Length of list b:", len(list(b)), "and size of set sb:", len(sb))
print("Length of list c:", len(list(c)), "and size of set sc:", len(sc))
print("Length of string s:", len(s), "and size of set ss:", len(ss))

# pause
input("\nHit return to continue"); print("\n", end='')

# and set membership
print("3 in set sa (3 in sa):", 3 in sa)
print("9 in set sa (9 in sa):", 9 in sa)

# pause
input("\nHit return to continue"); print("\n", end='')

# union
print("Set sa:", sa, "and set sb:", sb)
su1 = sa | sb
su2 = sa.union(sb)
print("Union: sa | sb:", su1)
print("Union: sa.union(sb):", su2)

# pause
input("\nHit return to continue"); print("\n", end='')

# intersection
print("Set sa:", sa, "and set sb:", sb)
si1 = sa & sb
si2 = sa.intersection(sb)
print("Intersection: sa & sb:", si1)
print("Intersection: sa.intersection(sb):", si2)

# pause
input("\nHit return to continue"); print("\n", end='')

# difference
print("Set sa:", sa, "and set sb:", sb)
sd1 = sa - sb
sd2 = sa.difference(sb)
print("Difference: sa - sb:", sd1)
print("Difference: sa.difference(sb):", sd2)

# pause
input("\nHit return to continue"); print("\n", end='')

# isdisjoint
print("Set sa:", sa, "and set sb:", sb, "and set sc:", sc)
sid1 = sa.isdisjoint(sb)
sid2 = sa.isdisjoint(sc)
print("Are they disjoint? sa.isdisjoint(sb):", sid1)
print("Are they disjoint? sa.isdisjoint(sc):", sid2)

# pause
input("\nHit return to continue"); print("\n", end='')

# add elements
print("Set sa:", sa, "and set sb:", sb)
sa.add(100)
print("Add an element (sa.add(100)):", sa)
sa.update(sb)
print("Add a bunch of elements (sa.update(sb)):", sa)

# pause
input("\nHit return to continue"); print("\n", end='')

# example of frozensets -- they are immutable
fa = frozenset(a)

print("Frozen set fa:", fa, "-- now add 100 (or try to)")
try:
    fa.add(100)
except Exception as msg:
    print("fa.add(100) failed --", msg)
else:
    print("Add an element (fa.add(100)):", fa)

# pause
input("\nHit return to continue"); print("\n", end='')

#
#now we're going to generate a word list -- we don't care how many
# times a word appears, though
#
# we also look for duplicate words in the test
#

# return True if there are duplicates in the list t, False if not
# do this with sets -- if the number of words in the list is the
# same as the number of elements in the set, there are no duplicates
# otherwise there are
def hasduplicates(t):
    return len(set(t)) != len(t)

# here's where we keep the words -- it's a set as we just care
# about the words, not how many times they occur
words = set()

#
# now we read the input, check each line for duplicates, and put
# the words in the line in the set (which is cumulative)
while True:
    try:
        # read the input and split it into words
        s = input("% ").split()
    # quit on EOF
    except EOFError:
        break
    # any other error -- print error message and quit
    except Exception as msg:
        print("Error --", msg)
        break

    # now report whether there are any dulicate words in the line
    # this is so we can see how sets handle duplicates
    if hasduplicates(s):
        print("Has duplicates")
    else:
        print("No duplicates")

    # now add the words
    words.update(s)

    # this also works
    for w in s:
        words.add(w)
#
# now print the words
#
# ...  in the order they are in the set
print("Now the words in the order they are in the set")
for i in words:
    print(i, end=' ')
print("\n\nNow the words in sorted order")
# ...  in sorted order
for i in sorted(words):
    print(i, end=' ')
print("")