check = set()
for i in range(len(names)):
count = 0
for j in range( len(names)):
if names[i] == names[j]:
count +=1
my_tup = (names[j], count)
check.add(my_tup)
print(check)
此代码没有给出正确的输出，如下所示： {('m', 2), ('m', 1), ('b', 1), ('p', 3), ('b ', 0), ('p', 2), ('b', 3), ('m', 0), ('m', 3), ('b', 2), ('p', 1)}
names = ["b", "b", "b", "m", "p", "p", "m"]
#made the set so that I can record the frequencies of each word only once,
#since it doesn't allow repetation
check = set()
for i in names:
#tuple, because it's hashable
my_tup = (i, names.count(i))
check.add(my_tup)
print(check)
此代码给出正确的输出，如下所示： {('m', 2), ('p', 2), ('b', 3)}