#
# this sorts a dictionary in a variety of ways
#
d = { "hello" : 2, "Goodbye" : 69, "gleep" : 21, "Howdy": -3 }

d["snork"] = -36

#
# first, just print it as stored
#
print("Dictionary entries, as stored:")
n = 1
for i in d:
    print("%d. key: '%s' --> value: '%d'" % (n, i, d[i]))
    n += 1

#
# now, sort them by key
#
print("\nDictionary entries, sorted by key:")
klist = d.keys()
n = 1
for i in sorted(klist):
    print("%d. key: '%s' --> value: '%d'" % (n, i, d[i]))
    n += 1

#
# same thing, but collapse the case
#
print("\nDictionary entries, sorted by key with collapsed case:")
klist = d.keys()
n = 1
for i in sorted(klist, key=str.lower):
    print("%d. key: '%s' --> value: '%d'" % (n, i, d[i]))
    n += 1

#
# sort them by key, but done by looking at the first element of
# each pair in the dictionary
#
print("\nDictionary entries, sorted by key in a different way:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: x[0]):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1

#
# same thing, but collapse the case
#
print("\nDictionary entries, sorted by key with collapsed case in a different way:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: x[0].lower()):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1

#
# now sort by increasing value
#
print("\nDictionary entries, sorted by (increasing) value:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: x[1]):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1

#
# now sort by decreasing value
#
print("\nDictionary entries, sorted by (decreasing) value:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: -x[1]):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1

#
# fun sort: by the fourth power of th value (this will put 2 before -3)
#
print("\nDictionary entries, sorted by the fourth power of the value:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: x[1]**4):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1

#
# sort by the reverse of each key
#
def revstr(x):
    return x[::-1]
    
print("\nDictionary entries, sorted by the reverse of the key:")
klist = d.keys()
n = 1
for i in sorted(klist, key=lambda x: revstr(x)):
    print("%d. key: '%s' --> value: '%d'" % (n, i, d[i]))
    n += 1

#
# sort by the reverse of each key; this time, it's using items
#
print("\nDictionary entries, sorted by the reverse of the key using items:")
ilist = d.items()
n = 1
for i in sorted(ilist, key=lambda x: revstr(x[0])):
    print("%d. key: '%s' --> value: '%d'" % (n, i[0], i[1]))
    n += 1