"""

Your RandomizedSet object will be instantiated and called as such:

obj = RandomizedSet()

param = obj.insert(val)

param = obj.remove(val)

param = obj.getRandom()

"""

import random

class RandomizedSet:

def __init__(self):

self.nums = []

self.val2idx = {}

def insert(self, val):

"""

Inserts a value to the set. Returns true if the set did not already contain the specified element.

:type val: int

:rtype: bool

"""

self.val2idx[val] = len(self.nums)

self.nums.append(val)

def remove(self, val):

"""

Removes a value from the set. Returns true if the set contained the specified element.

:type val: int

:rtype: bool

"""

if val not in self.val2idx:

return False

i = self.val2idx[val]

key = self.nums[-1]

self.val2idx[key] = i

self.nums[i] = self.nums[-1]

self.nums.pop()

del self.val2idx[val]

return True

def getRandom(self):

"""

Get a random element from the set.

:rtype: int

"""

i = random.randrange(len(self.nums))

return self.nums[i]