hash table

hashtable.js

class HashEntry {
   constructor(k, v) {
     this.key = k
     this.value = v
   }
  
   setValue(v) {
     this.value = v
   }
}

class HashTable {
  constructor(size = 20) {
    this.size = size
    this.table = [ ]
  }
  
  hash(key) {
    return key.length % this.size
  }
  
  find(hash, k) {
    if (!this.table[hash])
       return null
    
    const length = this.table[hash].length
    for (let i = 0; i < length; i++) {
      if (this.table[hash][i].key === k)
        return i
    }
    
    return null
  }
  
  remove(k) {
    const hash = this.hash(k)
    const index = this.find(hash, k)
    if (index === null)
      return false
      
    this.table[hash].splice(index, 1)
  }
  
  get(k) {
    const hash = this.hash(k)
    const index = this.find(hash, k)
    if (index === null)
      return undefined
      
    return this.table[hash][index].value
  }
  
  set(k, v) {
    const hash = this.hash(k)
    if (!this.table[hash])
      this.table[hash] = [ ]
      
    const index = this.find(hash, k)
    if (index === null) {
      this.table[hash].push(new HashEntry(k, v))
      return true
    }
    
    this.table[hash][index].setValue(v)
    return true
  }
}

const table = new HashTable()
table.set('k', 20)
table.set('v', 40)
table.set('deeeeee', 80)

console.log(table.get('k'), table.get('v'), table.get('d'))
table.remove('k')
console.log(table.get('k'))

console.log(JSON.stringify(table.table))