我就是这样，感觉没毛病

# Enter a code

d = {'Alice': [50, 61, 66], 'Bob': [80, 61, 66], 'Candy': [88, 75, 90]}

m = 0

for key in d.keys():

    m += 1

print(m)

n = 0

for x in d:

    n = n + 1

    print(x) #打印出来看看

print(n)

y = 0

for s in d.values():

    y += 1

    print(s)

print(y)

感觉可以