Exercise 6.2-2

6.2-2 Starting with the procedure MAX-HEAPIFY, write pseudocode for the procedure MIN-HEAPIFY(A, i), which performs the corresponding manipulation on a minheap. How does the running time of MIN-HEAPIFY compare to that of MAXHEAPIFY?

Answer 

The running time is the same we just need to find the smallest instead of the greatest.

Code in C++ (code is taken from a heap implementation I made, so A is not a parameter):

void Heap :: minHeapiFy ( unsigned index )
{
    unsigned child = getLeft ( index ) ;

    if ( child >= getHeapSize ( ) )
        return ;

    if ( child < getHeapSize ( ) - 1 && heapArray [ child ] > heapArray [ child + 1 ] )
        ++ child ;

    if ( heapArray [ index ] > heapArray [ child ] )
    {
        swap ( heapArray [ child ] , heapArray [ index ] ) ;
        minHeapiFy ( child ) ;
    }
}