【数据结构】二分查找

#include<iostream>
#include<algorithm>
using namespace std;
//自己写
typedef struct  LNode
{
	LNode *left;
	LNode *right;
	int Length;
	int Element[50];
}LNode,*Linklist;
int BinartSearch(Linklist Tbl,int k)
{
	int left, right, mid, NoFound = -1;
	left = 1;
	right = Tbl->Length;
	while (left <= right)
	{
		mid = (left + right) / 2;
		if (k < Tbl->Element[mid])
			right = mid - 1;
		else if (k > Tbl->Element[mid])
			left = mid + 1;
		else
			return mid;
	}
	return NoFound;
}
//stl
int Elem[50];
int a = binary_search(Elem, Elem + 50, 5);
int main()
{
	int a[100] = { 4,10,11,30,69,70,96,100 };
	int b = binary_search(a, a + 9, 4);//查找成功，返回1
	cout << "在数组中查找元素4，结果为：" << b << endl;
	int c = binary_search(a, a + 9, 40);//查找失败，返回0
	cout << "在数组中查找元素40，结果为：" << c << endl;
	int d = lower_bound(a, a + 9, 10) - a;
	cout << "在数组中查找第一个大于等于10的元素位置，结果为：" << d << endl;
	int e = lower_bound(a, a + 9, 101) - a;
	cout << "在数组中查找第一个大于等于101的元素位置，结果为：" << e << endl;
	int f = upper_bound(a, a + 9, 10) - a;
	cout << "在数组中查找第一个大于10的元素位置，结果为：" << f << endl;
	int g = upper_bound(a, a + 9, 101) - a;
	cout << "在数组中查找第一个大于101的元素位置，结果为：" << g << endl;
}