hash-table.js

// Hash Table

const hash = (key, size) => {
  let hashedKey = 0;

  for (let i = 0; i < key.length; i++) {
    hashedKey = key.charCodeAt(i)
  }

  return hashedKey % size;
}

class HashTable {
  constructor() {
    this.size = 20;
    this.buckets = Array(this.size);

    for (let i = 0; i < this.buckets.length; i++) {
      this.buckets[i] = new Map();
    }
  }
  insert(key, value) {
    let idx = hash(key, this.size);
    // set is a built in method on the map data structure
    this.buckets[idx].set(key, value);
  }

  remove(key) {
    let idx = hash(key, this.size);
    // get is also a built in method on the map data structure
    let deleted = this.buckets[idx].get(key);
    // delete is also a built in map method
    this.buckets[idx].delete(key)
    return deleted
  }

  search(key) {
    let idx = hash(key, this.size);
    return this.buckets[idx].get(key)
  }
};

const hashTable = new HashTable();

hashTable.insert('serena', 'moon');
hashTable.insert('amy', 'mercury');
hashTable.insert('rei', 'mars');
hashTable.insert('lita', 'jupiter');
hashTable.insert('mina', 'venus');
hashTable.insert('darien', 'tuxedo mask');

console.log(hashTable.search('rei'));
console.log(hashTable.search('lita'));
console.log(hashTable.search('serena'));

console.log(hashTable.remove('darien'));
console.log(hashTable.remove('mina'));
console.log(hashTable);