歸併排序(C語言)

void merge(int* arr,size_t left,size_t pi,size_t right)
{
	int i=left,j=pi+1,k=0;
	// 內部合併
	int temp[right-left+1];

	while(i<=pi && j<=right)
	{
		if(arr[i] < arr[j])
			temp[k++] = arr[i++];
		else
			temp[k++] = arr[j++];
	}

	while(i<=pi) temp[k++] = arr[i++];
	while(j<=right) temp[k++] = arr[j++];
	
	for(int i=0; i<=(right-left); i++)
	{
		arr[i+left] = temp[i];
	}
}
void _merge_sort(int* arr,size_t left,size_t right)
{
	if(left >= right) return;
	int pi = (left+right)/2;
	printf("%d %d\n",pi,arr[pi]);
	_merge_sort(arr,left,pi);
	_merge_sort(arr,pi+1,right);
	merge(arr,left,pi,right);
}