这题也没什么说的，各种增删用list就可以解决了，最后用random.choice从list中随机取一个返回
import random class RandomizedSet(object): def __init__(self): """ Initialize your data structure here. """ self.list1 = [] 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 """ if val not in self.list1: self.list1.append(val) return True else: return False 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 in self.list1: self.list1.remove(val) return True else: return False def getRandom(self): """ Get a random element from the set. :rtype: int """ return random.choice(self.list1)