Comparing Sorts Program Help and Hints

1. You can take code like this:
   
   if (theArray[currentIndex] > theArray[indexSoFar])
   
   and turn it into code like this:
   
   if (++c_count && (theArray[currentIndex] > theArray[indexSoFar]))
   
   The expression "++c_count" takes care of incrementing the counter and will not change the logic of the program. (Verify.)
   
   Notice that order is important here. It does not work to put "&& ++c_count" at the end of the original expression. (Why not?)
   
   You can use the same basic idea to take care of counts inside the conditions of if-statements or counts inside loop-conditions.
   
   
2. Use code like this:
   
   cout << "mergesort starting ... " ;
   cout.flush() ;
   mergesort(A, 0, howMany-1, c_count, m_count) ;
   cout << "done" << endl ;
   
   To mark when the program starts a sort and finishes it. If you don't use something like the cout.flush() command (on most computers) then the output may be buffered - and you won't see the "mergesort starting ..." part of the message until after the sort is completed!
   
   
3. It may be a good idea to make your counters unsigned long int. This will give you a little extra margin in case you come close to overflowing your counters. For example, you could declare your counters this way:
   
   unsigned long int c_count, m_count ;