380_Insert_Delete_GetRandom_O(1).py

# //这个解法站在python的角度看确实是O(1)

class RandomizedSet(object):
    def __init__(self):
        """
        Initialize your data structure here.
        """
        self.data = []

    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 in self.data:
            return False
        else:
            self.data.append(val)
            return True

    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.data:
            return False
        else:
            self.data.remove(val)
            return True

    def getRandom(self):
        """
        Get a random element from the set.
        :rtype: int
        """
        import random
        return random.choice(self.data)



        # Your RandomizedSet object will be instantiated and called as such:
        # obj = RandomizedSet()
        # param_1 = obj.insert(val)
        # param_2 = obj.remove(val)
        # param_3 = obj.getRandom()