C++趣味编程

折半查找。

#include <iostream>
using namespace std;
#define N 10
int main()
{
    int i,a[N]={-3,4,7,9,13,45,67,89,100,180},low=0,high=N-1,mid,k=-1,m;
    cout<<"a数组中数据如下"<<endl;
    for(int i=0;i<N;i++)
    {
        cout<<a[i]<<" "; 
     } 
    cout<<endl;
    cin>>m;
    while(low<=high)
    {
        mid=(low+high)/2;
        if(m<a[mid])
        {
            high=mid-1;
        }
        else
        {
            if(m>a[mid])
            low=mid+1;
            else
            {
                k=mid;
                break;
            }
        }    
    }
    if(k>=0)
    {
        cout<<m<<","<<k<<endl;
    }
    else
    {
        cout<<"no found"<<endl;
    }
    
}