alexhawkins

'use strict';
//######### EXAMPLE 1 #################/
// Implement function countDecrementing that takes a number `n` and logs numbers n to 0

var countDown = function(num) {
    if (num >= 0) {
        console.log(num);
        countDown(num - 1);
    }
};

alexhawkins

'use strict';

/*****************NATIVE forEACH*********************/

Array.prototype.myEach = function(callback) {
    for (var i = 0; i < this.length; i++)
        callback(this[i], i, this);
};

//tests

alexhawkins

/* SIMPLIFIED UNDERSCORE .EACH method*/

var _ = function(obj) {
    if (obj instanceof _) return obj;
    if (!(this instanceof _)) return new _(obj);
    this._wrapped = obj;
};

alexhawkins

//#######PLUCK#######

var myPluck = function(obj, propName) {
    var arr = [];
    for (var i = 0; i < obj.length; i++) {
        for (var prop in obj[i]) {
            if (prop === propName)
                arr.push(obj[i][prop]);
        }
    }

alexhawkins

arr = [7, 7, 9, 2, 45, 6, 34, 43, 2, 6, 8, 2, 4, 100, 100, 100, 23, 34, 4];

var uniq = function(arr) {
    return arr.filter(function(value, index, self) {
        // only returns uniq numbers. A duplicate will yield a different indexOf
        return self.indexOf(value) === index;
    }).sort(function(x, y) {
        return x - y;
    });
};

alexhawkins

var shuffle = function(arr) {
    var rand, temp;
    //loop through array and swap out value at random position
    //with value at iteration position of array
    for (var i = 0; i < arr.length; i++) {
        //generate random number between 0 and length of array.
        rand = Math.floor(Math.random() * arr.length);
        temp = arr[i]; //store value of arr[i] to swap later
        arr[i] = arr[rand]; //set arr[i] to random position value
        arr[rand] = temp; //replace with temp

alexhawkins

var cipher = function(str, num) {

    var code = 0,
        cipher = '';
    for (var i = 0; i < str.length; i++) {
        code = str.charCodeAt(i);
        //check lowercase
        if (code >= 97 && code <= 122) {
            code += num;

alexhawkins

 
//Recursive implementation of jSON.stringify;
var stringifyJSON = function(obj) {

    var arrOfKeyVals = [],
        arrVals = [],
        objKeys = [];

    /*********CHECK FOR PRIMITIVE TYPES**********/
    if (typeof obj === 'number' || typeof obj === 'boolean' || obj === null)

alexhawkins

var _ = {};


/*********IDENTITY**********/
_.identity = function(val) {
    return val;
};

/*********FIRST**********/
_.first = function(array, n) {

alexhawkins

/* RECURSION ( when a function invokes itself to solve a problem )
  
  All recursive functions have the following characteristics:
 
  1) The method is implemented using if-else logic that leads to 
     different cases. 
  2) One or more base/terminating cases(the simplest case) are
     used to stop the recursion ex. if (n === 0) stop
  3) Every recursive call reduces the original problem, bringing
     it increasingly closer to the terminating base case until