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Design HashMap - Hash Table - Easy - LeetCode - MiniTV

Design HashMap - Hash Table - Easy - LeetCode - मिनी टीवी

Design a HashMap without using any built-in hash table libraries.

To be specific, your design should include these functions:

put(key, value) : Insert a (key, value) pair into the HashMap. If the value already exists in the HashMap, update the value.
get(key): Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key.
remove(key) : Remove the mapping for the value key if this map contains the mapping for the key.

Example:

MyHashMap hashMap = new MyHashMap();
hashMap.put(1, 1);          
hashMap.put(2, 2);         
hashMap.get(1);            // returns 1
hashMap.get(3);            // returns -1 (not found)
hashMap.put(2, 1);          // update the existing value
hashMap.get(2);            // returns 1 
hashMap.remove(2);          // remove the mapping for 2
hashMap.get(2);            // returns -1 (not found) 

Note:

All keys and values will be in the range of [0, 1000000].
The number of operations will be in the range of [1, 10000].
Please do not use the built-in HashMap library.

public class MyHashMap {

    /** Initialize your data structure here. */
    int[] hasharray; 
    public MyHashMap() {
        hasharray = new int[1000000];
        Array.Fill(hasharray, Int32.MinValue);
    }
    
    /** value will always be non-negative. */
    public void Put(int key, int value) {
        hasharray[key] = value;
    }
    
    /** Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key */
    public int Get(int key) {
        if (hasharray[key]!=Int32.MinValue)
            return hasharray[key];
        return -1;
    }
    
    /** Removes the mapping of the specified value key if this map contains a mapping for the key */
    public void Remove(int key) {
        hasharray[key] = Int32.MinValue;
    }
}

/**
 * Your MyHashMap object will be instantiated and called as such:
 * MyHashMap obj = new MyHashMap();
 * obj.Put(key,value);
 * int param_2 = obj.Get(key);
 * obj.Remove(key);
 */

 


Time Complexity: O(1)

Space Complexity: O(n)