/**
* Quicksort that delegates to helper thread the sorting of a sub-array
* should a thread be available and if the problem size is sufficiently
* large enough to warrant such an action.
*
* @param ar array being sorted
* @param cmp comparison function to use
* @param helper context for helper thread
* @param left lower bound index position (inclusive)
* @param right upper bound index position (inclusive)
*/
void quickSort2(void **ar, int(*cmp)(const void *,const void *),
THREAD_INFO *helper, int left, int right) {
int p,n;
if (left < right) {
p = partition(ar, cmp, left, right);
n = p - left;
/** If helper already requested to help or problem too big, recurse. */
if (helpRequested || n >= helper->threshold) {
quickSort2(ar, cmp, helper, left, p-1);
} else {
/** initialize helper variables and ask for help. */
helper->left = left;
helper->right = p-1;
helpRequested = 1;
}
n = right - p;
if (helpRequested || n >= helper->threshold) {
quickSort2(ar, cmp, helper, p+1, right);
} else {
/** initialize helper variables and ask for help. */
helper->left = p+1;
helper->right = right;
helpRequested = 1;
}
}
}
/**
* Entry point for primary thread.
*
* Once synchronized, launches the primary sort routine.
*
* @param arg thread context
*/
void quickSortEntry(void *arg) {
THREAD_INFO *context = (THREAD_INFO *) arg;
/** Wait until all threads ready to go. */
pthread_barrier_wait(&barrier);
/**
* When we get here, all threads are synchronized. Note that
* numElements is a global int which stores number of elements.
*/
quickSort2(context->ar, context->cmp, context->helper,
0, numElements-1);
/** Stop Helper thread. */
done=1;
/** Now wait for all threads again before exiting. */
pthread_barrier_wait(&barrier);
}
int main(int argc, char* argv[])
{
int len = atoi(argv[1]);
int array[len],array2[len];
srand(time(NULL));
int i;
for(i=0;i<len;i++) {array[i]=rand()%10000; array2[i]=array[i];}
printf("排序前的数组---->\n");
for(i=0;i<len;i++) printf("%d ",array[i]); printf("\n");
quickSort(array,0,len-1);
printf("递归方法排序后的数组---->\n");
for(i=0;i<len;i++) printf("%d ",array[i]); printf("\n");
quickSort2(array2,len);
printf("循环方法排序后的数组---->\n");
for(i=0;i<len;i++) printf("%d ",array2[i]); printf("\n");
return 0;
}
