g0701_0800.s0705_design_hashset

Class MyHashSet

java.lang.Object

g0701_0800.s0705_design_hashset.MyHashSet

public class MyHashSet
extends Object

705 - Design HashSet.

Easy

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

Implement MyHashSet class:

• void add(key) Inserts the value key into the HashSet.
• bool contains(key) Returns whether the value key exists in the HashSet or not.
• void remove(key) Removes the value key in the HashSet. If key does not exist in the HashSet, do nothing.

Example 1:

Input

["MyHashSet", "add", "add", "contains", "contains", "add", "contains", "remove", "contains"]
[[], [1], [2], [1], [3], [2], [2], [2], [2]]

Output: [null, null, null, true, false, null, true, null, false]

Explanation:

MyHashSet myHashSet = new MyHashSet(); 
myHashSet.add(1); // set = [1] 
myHashSet.add(2); // set = [1, 2] 
myHashSet.contains(1); // return True 
myHashSet.contains(3); // return False, (not found) 
myHashSet.add(2); // set = [1, 2] 
myHashSet.contains(2); // return True 
myHashSet.remove(2); // set = [1] 
myHashSet.contains(2); // return False, (already removed)

Constraints:

• 0 <= key <= 106
• At most 104 calls will be made to add, remove, and contains.

Constructor Summary

Constructors

Constructor and Description
MyHashSet()

Method Summary

Modifier and Type	Method and Description
void	add(int key)
boolean	contains(int key)
void	remove(int key)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

MyHashSet

public MyHashSet()

Method Detail

add

public void add(int key)

remove

public void remove(int key)

contains

public boolean contains(int key)