Solution: Insert Delete GetRandom O(1)

Explore how to build a custom data structure that inserts, deletes, and retrieves random elements efficiently. Understand the combination of arrays and hash maps to achieve constant average time complexity for all operations, and apply this knowledge to optimize data handling in coding interviews.

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Statement
Solution
- Naive approach
- Optimized approach using an array and a hash map

Statement

Implement a Random Set data structure that can perform the following operations:

Constructor(): This initializes the Random Set object.
Insert(): This function takes an integer, data, as its parameter and, if it does not already exist in the set, add it to the set, returning TRUE. If the integer already exists in the set, the function returns FALSE.
Delete(): This function takes an integer, data, as its parameter and, if it exists in the set, removes it, returning TRUE. If the integer does not exist in the set, the function returns FALSE.
GetRandom(): This function takes no parameters. It returns an integer chosen at random from the set.

Note: Your implementation should aim to have a running time of $O(1)$ (on average) for each operation.

Constraints:

$-2^{31} \leq$ data $\leq 2^{31}$
No more than $2 \times 10^5$

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