二分法查找

#include <iostream>
using namespace std;
#define  TOTAL_COUNT 1001
bool bin_search(int a[],int n,int key)
{
int low,hight,mid;
low = 0;
hight = TOTAL_COUNT -1;  //最高位减一
mid = (low+hight)/2;
while(low<hight)
{
if ( a[mid] == key )
{
cout << "Find Key  " << key << endl;
return true;
}
if ( a[mid] > key )
{
hight = a[mid];
}
if ( a[mid] < key )
{
low = a[mid+1];
}
mid = (low+hight)<<1; //防止溢出采用移位操作
}
cout << "Not Find Key  " << key << endl;
return false ;
}
int main()
{
int a[TOTAL_COUNT];
for ( int i=0;i< TOTAL_COUNT;i++)
{
a[i] = i;
}
bin_search(a,TOTAL_COUNT,999);
getchar();
}