二分查找法递归和非递归实现

//非递归实现
int BinarySearch(int A[], int length, int number)
{
	if(A==NULL || length<=0)
		return -1;
	int start=0;
	int end=length-1;
	
	while(start<end)
	{
		int mid=(start+end)/2;
		if(A[mid]==number)
			return mid;
		else
			if(A[mid]>number)
			{
				end=mid-1;
			}
			else
				start=mid+1;
	}
	return -1;

}
//递归实现
int BinarySearch(int A[], int start, int end,int number)
{
	if(A==NULL || start<end||start<0)
		return -1;
	int mid=(start+end)/2;
	
	if(A[mid]>number)
		return BinarySearch(A,start,mid-1,number);
	if(A[mid]<number)
		return BinarySearch(A,mid+1,end,number);
	if(A[mid]==number)
		return mid;
}