705.设计哈希集合

// 使用数组做hash
/**
* Initialize your data structure here.
*/
var MyHashSet = function () {
  this.hashContent = [];
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.add = function (key) {
  const data = this.hashContent;
  for (let i = 0; i < data.length; i++) {
    if (data[i] === key) return null;
  }
  data[data.length] = key;
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.remove = function (key) {
  const data = this.hashContent;
  for (let i = 0; i < data.length; i++) {
    if (data[i] === key) data.splice(i, 1);
  }
};

/**
 * Returns true if this set contains the specified element 
 * @param {number} key
 * @return {boolean}
 */
MyHashSet.prototype.contains = function (key) {
  const data = this.hashContent;
  for (let i = 0; i < data.length; i++) {
    if (data[i] === key) return true;
  }
  return false;
};

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

/**
 * Initialize your data structure here.
 */
var MyHashSet = function () {
  this.hashContent = {};
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.add = function (key) {
  this.hashContent[key] = true;
};

/** 
 * @param {number} key
 * @return {void}
 */
MyHashSet.prototype.remove = function (key) {
  this.hashContent[key] && delete this.hashContent[key];
};

/**
 * Returns true if this set contains the specified element 
 * @param {number} key
 * @return {boolean}
 */
MyHashSet.prototype.contains = function (key) {
  if (this.hashContent[key]) return true;
  return false;
};

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