mathball/lib/deficient/index.js

A JavaScript library for Competitive Programming

'use strict';

var validate = require('../validation/positive-integer');

/**
 * Find all divisors of a positive number and return an array of the same
 */
var findDivisors = function findDivisors(num) {
	var divisorsArr = [0];

	if (num === 1) {
		divisorsArr = [0];
	} else {
		for (var i = 1; i < num - 1; i++) {
			if (num % i === 0) {
				divisorsArr.push(i);
			}
		}
	}

	return divisorsArr;
};

/**
 * add all divisors
 */
var addAllDivisors = function addAllDivisors(arr) {
	var add = function add(total, num) {
		return total + num;
	};
	return arr.reduce(add);
};

exports.check = function (num) {
	validate(num, 'deficient');
	var divisors = findDivisors(num);
	var sum = addAllDivisors(divisors);

	return sum < num ? true : false;
};

// console.log(d(10));