6-7-1.cpp

学习c++的ppt

#include <iostream.h>
#include <stdlib.h>
class  BinSearch   {
    private:
         double  *Plist;
    public:
         BinSearch(double *list, int  n)  
         {    Plist = new double[n];
               for(int i=0; i < n; i ++)  Plist[i] = list[i];
         }
         ~BinSearch()
         {    delete  []Plist;
         }
         void  BinFind(int, int, double);
};  
void  BinSearch::BinFind(int low, int high, double  x)
{     int  mid = (low+high)/2;
      if(Plist[mid] == x)  {
          cout << "the position is: " << mid << endl;
          return;
      }  
      else if(low >= high)  {
          cout << x << " is not found !" << endl;
          return;
      } 
      else if(x > Plist[mid])
             BinFind(low+1, high, x);
      else  
             BinFind(low, high-1, x);
}
void  main()
{    double  a[] = {1.1, 1.3, 1.5, 1.7, 1.9, 
                                2.1, 2.3, 2.5, 2.7, 2.9};
       double  x = 2.4;
       int  low = 0,  high = 9;
       BinSearch    bs(a, 10);
       bs.BinFind(low, high, x);
}