/* library for output */
#include <iostream>

/* libraries for the random number generator */
#include <stdlib.h>
#include <time.h>

using namespace std;

// heapsort code works for all data types,
// including user defined types,
// provided operator '>' is overloaded

/* function prototypes*/
template <typename T>
void percDown(T array [], int hole, int size) ;

template <typename T>
void printArray(T array [], int length) {
    cout << "[";
    
    for (int i=0 ; i<length ; i++)
        cout << array[i] << " ";

    cout << "]\n";
}

/** Transpose entries at i and j in an array */
template <typename T>
void swapReferences(T array [], int i, int j) {
    T tmp = array[i];
    array[i] = array[j];
    array[j] = tmp;
}

/** Heap sort method. Modifies array so that it is in sorted order */
template <typename T>
void heapSort(T array [], int length) {
    // Build Heap
    for (int i=length/2 ; i>=0 ; i-- ) {
        percDown(array, i, length);
    }

    //printArray(array, length);

    for (int i=length-1 ; i>0 ; i-- ) {
        swapReferences( array, 0, i ); // deleteMax
        percDown( array, 0, i); // Maintain heap ordering property
    }
}

/** Percolate down method. The object to be percolated is at
 *  array[hole], and the current heap size (number of elements in
 *  the heap) is given. */
template <typename T>
void percDown(T array [], int hole, int size) {
        
    // YOUR CODE HERE

}

/** Test driver method. */
int main(int argc, char * argv []) {
    //-------------------------------------------------
    cout << "\nTest 1:  array of 39 random integers\n";
    int arrSize = 39;
    int a[arrSize];

    /* initialize random number generator */
    /* change the seed to the random number generator,
       based on the time of day */
    srand (time ((time_t *) 0) );

    for (int i=0 ; i<arrSize ; i++)
        a[i] = (int) (100.0 * rand() / ((double) RAND_MAX));

    cout << "Before: \n";
    printArray<int>(a, arrSize);

    heapSort<int>(a, arrSize);

    cout<< "After:\n";
    printArray<int>(a, arrSize);
    
    //-------------------------------------------------
    cout << "\n\nTest 2:  array of 26 letters in descending order\n";
    
    /* initialize character array */
    char alpha[27] = "zyxwvutsrqponmlkjihgfedcba";

    cout << "Before: \n";
    printArray<char>(alpha, 26);

    heapSort<char>(alpha, 26);

    cout<< "After:\n";
    printArray<char>(alpha, 26);
 
    //-------------------------------------------------
    cout << "\n\nTest 3:  array of 25 doubles in ascending order\n";
    
    /* initialize double array */
    double reals[25];
    for (int i=0 ; i<arrSize ; i++)
       reals[i] = (double) i * 0.5;

    cout << "Before: \n";
    printArray<double>(reals, 26);

    heapSort<double>(reals, 26);

    cout<< "After:\n";
    printArray<double>(reals, 26);
}