
#include <stdio.h>
#include <time.h>
#include <stdlib.h>

#define ARRAY_SIZE 1000

int test_array[ARRAY_SIZE];

int compare(int *a,int *b)
{
    return(*a-*b);
}

main()
{
    int i;
    time_t start_time;
    time_t stop_time;

    for ( i=0 ; i<ARRAY_SIZE ; i++ )
        test_array[i] = rand();
    time( &start_time );
    qsort( test_array, ARRAY_SIZE, sizeof(int), compare );
    time( &stop_time );
    printf( "%f seconds elapsed.\n",
           difftime(stop_time,start_time) );
    for ( i=0; i<ARRAY_SIZE-1 ; i++ )
        if ( test_array[i] > test_array[i+1] )
            printf( "Mismatch at position %d\n", i );
}

           A Driver Program to Test Quicksort Performance
           

