Update README.md

unit_01/w02d02/morning_exercise/README.md

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 # W02D02 Morning Warmup
+
 ![Cat Programmer](http://s2.quickmeme.com/img/99/9903c7c14add3fd0758b7b5b80c24d48101f296f13ce34736799a82c71f61bc2.jpg)
 
-####Exercises 1: Find a value in a given array
- - Write a function `searchArray` that takes an array and value as parameters and searches the array for the given value. If the value is in the array, return `true`, otherwise return '-1'.
-```javascript
-var nums = [1,2,3,4,5]
-searchArray(nums, 3) => true
-searchArray(nums, 6) => -1
+
+
+# JAVASCRIPT ITERATORS
+
+#####`.forEach`, `.map`, and `.reduce`
+
+Javascript iterators are like loops. They step (or iterate) over each item in an array. Iterators perform operations according to conditions specified in a callback.
+
+# .forEach
+
+`.forEach` is the basic iterator, all it does is step through each item in an array.
+
+#### EXAMPLE:
+
 ```
-Here is some starter code:
-```javascript
-var searchArray = function(array,value) {
+arr = [8, 8, 8, 8, 8, 8, 8, 8];
+
+arr.forEach(function(n) {
+	console.log(n + 1);
+});
+
+=> Prints a bunch of 9s to the console
+
+```
+
+
+##### EXERCISE:
+- Log each word in `words` in upper case using `.forEach.`
 
-};
 ```
+words = ["Ho", "Chi", "Minh", "City", "was", "once", "known", "as", "Prey", "Nokor"];
+```
+
+
+
+
+# .map
 
+`.map` is like `.forEach` but it returns a new array with the selections and / or transformations applied in the iterator. `.map` saves to a new array and does not alter the original array.
 
-#### Exercises 2: [Permutation](https://en.wikipedia.org/wiki/Permutation)
 
-- Given two strings, write a method to decide if one is a permutation of the other
+EXAMPLE:
+
+```
+var new_arr = arr.map(function(n) {
+	return n += n / 2
+});
+
+=> [12, 12, 12, 12, 12, 12, 12, 12]
+```
+
+####EXERCISE:
+
+```
+more_words = ["Joe", "Overreats", "Eggs"];
+```
+
+- Map to a new array that stores only the first letter from each word in `more_words`.
 
-Note: If you were given this problem in an inteview, important things to ask your interviewer would be:
-- Is this case sensitive (ex: is `God` different from `dog`)?
-- Is whitespace significant? (for this question, the white space is not important)
+Expected result:
 
+```
+["J", "O", "E"]
+```
+
+...
+
+# .reduce
+
+`.reduce` iterates over the elements in an array and smooshes them together into a single variable according to the instructions in the iterator. Like `.map`, it returns a new value and does not alter the original array.
+
+#### EXAMPLE: 
+
+Add together all numbers in an array:
+
+```
+new_value = arr.reduce(function(sum, n){
+	return sum += n
+});
+
+=> 64
+```
+
+
+#### EXERCISE: 
+```
+arr = [8, 8, 8, 8, 8, 8, 8, 8];
+```
+
+- Return the product of the numbers in `arr`.
+
+
+
+...
+
+#### EXERCISE:
+
+Using both `.map` and `.reduce`, find the total sheepCount of sheep shorn by sheep shearers at the 1623 Sheep Shearing Feast:
+
+```
+var sheepShearers = [
+    {
+        name: "Tim",
+        age: 20,
+        sheepCount: 18
+    },
+    {
+        name: "C3PO",
+        age: 200,
+        sheepCount: 320
+    },
+    {
+        name: "Cousin It",
+        age: Infinity,
+        sheepCount: 2900
+    }
+];
+```
+
+```
+=> 3238
+```
+
+
+
+
+
+#### EXTRA TIME: Find a value in a given array
+ - Write a function `searchArray` that takes an array and value as parameters and searches the array for the given value. If the value is in the array, return `true`, otherwise return '-1'.
 ```javascript
-isPermutation(`cat top`, `tap pat`) => false
-isPermutation(`cat top`, `tot cap`) => true
+var nums = [1,2,3,4,5]
+searchArray(nums, 3) => true
+searchArray(nums, 6) => -1
 ```
 Here is some starter code:
 ```javascript
-var isPermutation = function(str1, str2) {
+var searchArray = function(array,value) {
 
 };
 ```