Implementation of HashMap with Constant Time Operations

Design a data structure that effectively stores a key-value mapping and performs specific operations in constant time.

Explanation:

Your data structure should allow the following operations:

1. INSERT(key, value): Add a new (key, value) pair if key does not already exist, or update the value if it does. It does not return anything.
2. DELETE(key): Remove the key from storage. It returns nothing.
3. SEARCH(key): Check if a key exists. Return true if it does, otherwise false.
4. GET(key): Retrieve the value associated with the key. Return -1 if the key does not exist.
5. GET_SIZE(): Return the total number of key-value pairs.
6. IS_EMPTY(): Return true if storage is empty, otherwise false.

Input:

int N

Output:

varies based on operation type

Example:

Operations performed:

N = 6
1 insert key1 100
1 insert key2 200
4 get key1
5 get-size
2 delete key1
3 search key1

Expected Output:

200
2
false

Constraints:

• 1 <= N <= 10^5
• 1 <= T <= 3
• 1 <= V <= 10^5

Note:

• Key is a string and value is an integer.
• Value can never be -1.