HashSet.java

// Time Complexity : O(1) for push, O(1) for min and O(1) for peek
// Space Complexity : O(n)
// Did this code successfully run on Leetcode : Yes
// Any problem you faced while coding this :No


class MyHashSet {

    private boolean[][] storage;
    private int buckets;
    private int bucketItems;    

    public MyHashSet() {

        this.buckets = 1000;
        this.bucketItems = 1000;
        this.storage = new boolean[buckets][];
    }

    private int hash1(int key) {
        return key % this.buckets;
    }

    private int hash2(int key) {
        return key/this.buckets;
    }
    
    public void add(int key) {
        int bucket = hash1(key);
        int bucketItem = hash2(key);

        if(storage[bucket] == null) {

            if(bucket  == 0){
                storage[bucket] = new boolean[bucketItems+1];
            } else {
            storage[bucket] = new boolean[bucketItems];
            }
        }
        storage[bucket][bucketItem] = true;
    }
    
    public void remove(int key) {
        
        int bucket = hash1(key);
        int bucketItem = hash2(key);
        
        if(storage[bucket] == null) {
            return;
        }

        storage[bucket][bucketItem] = false;
    }
    
    public boolean contains(int key) {
        
        int bucket = hash1(key);
        int bucketSize = hash2(key);

        if(storage[bucket] == null) {
            return false;
        }

        return storage[bucket][bucketSize]; 

    }
}

/**
 * Your MyHashSet object will be instantiated and called as such:
 * MyHashSet obj = new MyHashSet();
 * obj.add(key);
 * obj.remove(key);
 * boolean param_3 = obj.contains(key);
 */