title: Trying to understand max heapify
body: <p>I tried watching <a href="http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-006-introduction-to-algorithms-fall-2011/lecture-videos/lecture-4-heaps-and-heap-sort/" rel="noreferrer">http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-006-introduction-to-algorithms-fall-2011/lecture-videos/lecture-4-heaps-and-heap-sort/</a> to understand heaps and heapsort but did not find this clear.</p>
  
  <p>I do not understand the function of max-heapify. It seems like a recursive function, but then somehow it's said to run in logarithmic time because of the height of the tree.</p>
  
  <p>To me this makes no sense. In the worst case, won't it have to reverse every single node? I don't see how this can be done without it touching every single node, repeatedly.</p>