title: 2-way Merge Sort and Merge Sort
body: <p>How 2-way Merge Sort are different from Merge Sort recursively?</p>
  
  <hr>
  
  <p>Suppose there are 5 number to be sorted 8,9,1,6,4
  In Merge Sort we divide like this
  Step1:   {8,9,1}             {6,4}</p>
  
  <p>Step2: {8,9}     {1}     {6}      {4}</p>
  
  <p>Step3:{8} {9}    {1}      {6}      {4}</p>
  
  <p>Now Merge</p>
  
  <p>Step4:  {8,9}    {1}         {4,6}</p>
  
  <p>Step5:    {1,8,9}            {4,6}</p>
  
  <p>Step6:          {1,4,6,8,9}</p>
  
  <p>But in 2 way merge sort, we divide the array in 2 elements each(but according to wikipedia , before merging every 2 element parts need to be sorted.<a href="https://en.wikipedia.org/wiki/K-way_merge_algorithm" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/K-way_merge_algorithm</a> )So, it also starts from single element and merge them
  right?
  So, steps for array :8,9,1,6,4</p>
  
  <p>Step1:{8,9}  {1,6}    {4} [that is odd element merge at last]</p>
  
  <p>Step2:  {1,6,8,9}.    {4}</p>
  
  <p>Step3:     {1,4,6,8,9}</p>
  
  <p>So, number of steps reduces here. Then what will be algorithm for it? Is 2-way merge sort merge sort more efficient than merge sort?</p>