Two Sum III - Data structure design

Description

null

Solution(javascript)

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

/**
 * Add the number to an internal data structure.. 
 * @param {number} number
 * @return {void}
 */
TwoSum.prototype.add = function(number) {
    this.map[number] = (this.map[number] || 0) + 1
};

/**
 * Find if there exists any pair of numbers which sum is equal to the value. 
 * @param {number} value
 * @return {boolean}
 */
TwoSum.prototype.find = function(value) {
    return Object.keys(this.map).some(key => {
        const num1 = Number(key)
        const num2 = value - num1
        if(num1===num2) {
            if(this.map[num1] >= 2) {
                return true   
            }
        } else if(this.map[num2] >= 1) {
            return true
        }
        return false
    })
};

/** 
 * Your TwoSum object will be instantiated and called as such:
 * var obj = new TwoSum()
 * obj.add(number)
 * var param_2 = obj.find(value)
 */