二分法查找算法——DEMO

// 二分法查找

 

 

#include <iostream>

using namespace std;

int main()
{
    const int N = 10;
    int i, iIndex;
    bool isFound =false;
    int a[N] = {-60, -57,-9, 1, 3, 8, 10, 19, 20, 120};

    cout<< "Serial:\n";
    for ( i = 0; i< N; i++ )
    {
       cout.width(5);
       cout << i;
    }
    cout<< endl;

    cout<< "Data:\n";
    for ( i = 0; i< N; i++ )
    {
       cout.width(5);
       cout <<a[i];
    }
    cout<< endl;

    int SearchObj;
    cout<< "Which object will be search?";
    cin>> SearchObj;
    int Head = 0, Tail = N,Middle = (Tail-Head)/2;;
    int iFoundCount =0;
    while ( !isFound&& iFoundCount <N)
    {
       if ( SearchObj > a[Middle])
       {
           Head =Middle;
           Middle =Head + (Tail-Head)/2;
       }
       else
       {
           if (SearchObj < a[Middle] )
           {
              Tail = Middle;
              Middle = Tail -(Tail-Head)/2;
           }
           else
           {
              isFound = true;
              iIndex = Middle;
           }
       }
       iFoundCount++;
    }

    if ( isFound )
    {
       cout << "Foundobject index is: " << iIndex<< endl;
    }
    else
    {
       cout << "Cannotfind!" << endl;
    }
    cout<< "Search times:"<< iFoundCount;

    return 0;
}

 

// 百度里可以搜到很多种，都是有问题的，本算法本经人亲自测试验证无误。