Heap Sort

This is kind of an upgraded version of selection sort. They are similar because heapsort breaks down the input data into two groups, sorted and unsorted, and builds the sorted group one number at a time. Where they differ, is where heapsort uses, a heap, to build the unsorted group so its not blindly finding each number, one at a time. Heapsort adds the largest number from the unsorted group to the sorted group, then rebuilds the heap and repeats the process, adding the highest number to the sorted group.