Internals & Memory

Preview — 3 of 10 questions

What happens when the following code runs?

javascript

from array import array

arr = array('i', [1, 2, 3])
arr.append(4)
print(arr)
arr.append(2.5)

Aarray('i', [1, 2, 3, 4, 2.5])

Barray('i', [1, 2, 3, 4]), then TypeError: 'float' object cannot be interpreted as an integer

Carray('i', [1, 2, 3, 4]), then 2.5 is silently truncated and appended as 2

Darray('i', [1, 2, 3, 4]), then ValueError: array item exceeds capacity

What is the output of the following code?

javascript

d = {"a": 1, "b": 2, "c": 3}
del d["a"]
d["a"] = 10

print(list(d.keys()))

A['a', 'b', 'c']

B['a', 'c', 'b']

C['b', 'c', 'a']

D['c', 'b', 'a']

What is the output of the following code?

javascript

from collections import Counter

a = Counter(apple=3, banana=2)
b = Counter(apple=1, banana=4)

diff = a - b
a.subtract(b)

print(diff)
print(a)

ACounter({'apple': 2, 'banana': -2}) then Counter({'apple': 2, 'banana': -2})

BCounter({'apple': 2}) then Counter({'apple': 2})

CCounter({'apple': 2}) then TypeError: 'Counter' object has no attribute 'subtract'

DCounter({'apple': 2}) then Counter({'apple': 2, 'banana': -2})

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