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ProblemsDesign HashSet

Design HashSet

Easy
HashingDesign

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, 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]

 

Constraints:

  • 0 <= key <= 106
  • At most 104 calls will be made.

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