Hash Set Operations

Problem

Simulate a hash set supporting add, remove, and contains.

operations contains "add", "remove", or "contains"; values provides the key. add records None, remove records True when the key was present and False otherwise, and contains records a boolean.

Return the list of recorded results.

Hint

Python's built-in set is fine: add, discard, and the in operator are all O(1) average.

Test cases

case 1

in: [["add","add","contains","remove","contains"],[1,2,2,2,2]]

expected: [null,null,true,true,false]

case 2

in: [["remove","add","contains"],[5,5,5]]

expected: [false,null,true]

case 3

in: [["add","add","add","contains","contains"],[1,1,2,1,2]]

expected: [null,null,null,true,true]

case 4

in: [["contains"],[7]]

expected: [false]

Starter codePython

def hash_set_ops(operations, values):
    # Your code here
    pass

4 test cases · run your code against them in the editor