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Algorithms & data structures

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Algorithms & data structures medium

Implement Insert Delete GetRandom O(1) in Python

Build a RandomizedSet class that supports insert, delete, and get_random in average O(1) time using a list and a dictionary mapping values to indices.

randomized-set o1-lookup hash-map
Python 
import random

class RandomizedSet:
    def __init__(self):
        self.values = []
        self.index_map = {}

    def insert(self, val):
        if val in self.index_map:
            return False
        self.index_map[val] = len(self.values)
        self.values.append(val)
        return True

    def delete(self…
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