example complete

Author: kelvinlauKL

Mergesort/README.markdown

@@ -10,16 +10,28 @@ is to **divide and conquer**; To divide a big problem into smaller chunks and so
 - Keep splitting the resulting piles until you can't anymore; In the end, you will have *n* piles with 1 number in each pile
 - Begin to **merge** the piles together by sequentially pairing a pile with another pile. During each merge, you want to sort the contents in order
 
-### An example
+## An example
 
-Let's say the numbers to sort are `[1, 7, 4 , 5, 9]`. This is your unsorted pile. Our goal is to keep splitting the pile until you can't anymore. 
+### Splitting
 
-Split the array into two halves - `[1, 7,]` and `[4, 5, 9]`. Can you keep splitting them? Yes you can!
+Let's say the numbers to sort are `[2, 1, 5 , 4, 9]`. This is your unsorted pile. Our goal is to keep splitting the pile until you can't anymore. 
 
-Focus on the left pile. `[1, 7]` will split into `[1]` and `[7]`. Can you keep splitting them? No. Time to check the other pile.
+Split the array into two halves - `[2, 1,]` and `[5, 4, 9]`. Can you keep splitting them? Yes you can!
 
-`[4, 5, 9]` splits to `[4]` and `[5, 9]`. Unsurprisingly, `[4]` can't split into anymore, but `[5, 9]` splits into `[5]` and `[9]`. 
+Focus on the left pile. `[2, 1]` will split into `[2]` and `[1]`. Can you keep splitting them? No. Time to check the other pile.
+
+`[5, 4, 9]` splits to `[5]` and `[4, 9]`. Unsurprisingly, `[5]` can't split into anymore, but `[4, 9]` splits into `[4]` and `[9]`. 
 
 The splitting process ends with the following piles:
 
-`[1]` `[7]` `[4]` `[5]` `[9]`
+`[2]` `[1]` `[5]` `[4]` `[9]`
+
+### Merging
+
+Now that you've split the array, you'll **merge** the piles together **while sorting them**. Remember, the idea is to solve many small problems rather than a big one. For each merge iteration you'll only be concerned at merging one pile with another.
+
+Given `[2]` `[1]` `[5]` `[4]` `[9]`, the first pass will result in `[1, 2]` and `[4, 5]` and `[9]`. Since `[9]` is the odd one out, you can't merge it with anything during this pass. 
+
+The next pass will merge `[1, 2]` and `[4, 5]` together. This results in `[1, 2, 4, 5]`, with the `[9]` left out again since it's the odd one out. 
+
+Since you're left with 2 piles, `[9]` finally gets it's chance to merge, resulting in the sorted array `[1, 2, 4, 5, 9]`.