Updates README and fixes bug in gcf

Author: beth

README.md

@@ -18,3 +18,5 @@ There are 12 problems as of 7/18. Solution branch will appear on 7/22.
 
 If you are attending the in person session, please also have this tab open: 
 [Understanding Check](https://pollev.com/bigcavern281)
+
+[Slides from Review Session](http://slides.com/bethjohnson/algorithmic-complexityreview-3-4/)

algo-time-complexity-review.js

@@ -55,7 +55,7 @@ function gcf(num1, num2){
   if (num1 > num2){ //this ensures num1 is the smaller number
     var temp = num1;
     num1 = num2;
-    num2 = num1;
+    num2 = temp;
   }
   for (var i = num1; i > 1; i--){
     if (num1 % i === 0 && num2 % i === 0){
@@ -170,7 +170,7 @@ function findColor(quadTree, coordinates){
   if (!Array.isArray(quadTree.color)){
     return quadTree.color;
   } else {
-    var quadrant = findQuadrant(quadTree, coordinates);
+    var quadrant = findQuadrant(quadTree, coordinates); 
     if (quadrant === "NE") {
       return findColor(quadTree.color[0], coordinates);
     }