title: 3 partition mergesort
body: <p>My professor assigned my class with implementing mergesort in arrays with 3-part partitioning and merging.</p>
  
  <p>That was the exact question from the professor. Problem is I have found no such thing as a 3-way mergesort I only know of a 3-way quicksort so I thought that he probably meant to take an array, split it into 3 parts and then mergesort those 3 parts together and I'm doing this by mergesorting the first 2 parts together and then mergesorting the combined part with the 3rd part.</p>
  
  <p>Did I think correctly and did I do the right thing (already implemented but I'm not posting the code since it doesn't have anything to do with my question) or have I understood wrong and there is something like a 3-way mergesort that I am not aware of.</p>
  
  <p>The professor tends to give us assignments that have to do with stuff that we have not learned yet that's why I'm so sceptical about this and I looked as much as I could in Google etc.</p>