C++二分查找算法实例

#include <iostream>using namespace std;int search(int *p,int length,int key);int search1(int *p,int length,int key);int main(){  cout << "Hello world!" << endl;  int a[] = {1,2,3,4,5,6,7,8,8,8,9,10,11,12,13,14};  int len = sizeof(a)/sizeof(int);  int pos = search1(a,len,8);  cout << pos << endl;  return 0;}int search1(int *p,int length,int key){  int left=0;  int right=length-1;  while(left<=right)  {    int mid = (left+right)/2;    if(p[mid]>=key)    {      right = mid-1;    }else    {      left = mid+1;    }  }  if(left<length && p[left]==key)    return left;  return -1;}int search(int *p,int length,int key){  int left=0;  int right = length -1;  while(left<=right)  {    int mid = (left+right)/2;    if(p[mid]==key)    {      return mid;    }    if(p[mid] > key)    {      right = mid+1;    }    if(p[mid]<key)    {      left=mid-1;    }  }  return -1;}