solution.js

/**
 * Initialize your data structure here.
 */
var MyHashMap = function() {
    this.buckets = new Array( )
    this.buckets.fill(null)
};

/**
 * value will always be positive. 
 * @param {number} key 
 * @param {number} value
 * @return {void}
 */
MyHashMap.prototype.put = function(key, value) {
    this.buckets[key - 1] = value
};

/**
 * Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key 
 * @param {number} key
 * @return {number}
 */
MyHashMap.prototype.get = function(key) {
    return this.buckets[key - 1] === null ? -1 : this.buckets[key - 1]
};

/**
 * Removes the mapping of the specified value key if this map contains a mapping for the key 
 * @param {number} key
 * @return {void}
 */
MyHashMap.prototype.remove = function(key) {
    this.buckets[key - 1] = null
};

/** 
 * Your MyHashMap object will be instantiated and called as such:
 * var obj = Object.create(MyHashMap).createNew()
 * obj.put(key,value)
 * var param_2 = obj.get(key)
 * obj.remove(key)
 */