//二分查找法(非遞歸調用)erfenfa2.cpp
#include<iostream.h>
#include<iomanip.h>
void binsrch(int a[],int n,int x)
{int mid,top=0,bot=n-1,i,find=0,m=0;
 do {
  m=m+1;
  mid=(top+bot)/2;
  if(a[mid]==x)
   {cout<<x<<"在序列中找到!\n";find=1;}
  else if(x<a[mid]) bot=mid-1;
  else if(x>a[mid]) top=mid+1;
 }while((top<=bot)&&(find==0));
 if(find==0) cout<<x<<"在序列中未找到!\n";
 cout<<"查找次數:"<<m<<endl;}
void main()
{cout<<"erfenfa2運行結果:\n";
 int b[]={1,3,5,7,9,10,12,15,17,19};
 int x=9,n=10;
 cout<<"輸入要查找的x:";cin>>x;
 cout<<"查找結果:\n";
 binsrch(b,n,x);
 cin.get();cin.get();}