zoj 1760 查找

http://acm.zju.edu.cn/onlinejudge/showProblem.do?problemId=760

撸了个二分查找

 #include<iostream>
 #include<cmath>
 #include<iomanip>
 #include<algorithm>
 using namespace std;

 int bs(int a[],int n,int len)
 {
           int lo = ,hi = len-,mid = (lo+hi)/;
           while(lo<=hi)
           {
                     if(n<a[mid])
                     {
                               hi = mid -;
                               mid = (lo+hi)/;
                     }
                     else if(n>a[mid])
                     {
                               lo = mid +;
                               mid = (lo+hi)/;
                     }
                     else
                               return mid;
           }
           if(lo>hi)
                     return -;
 }

 int main()
 {
           int a[];
           int x;
           while(cin>>x && x!=-)
           {
                     int i = ;
                     a[] = x;
                     while(cin>>a[i])
                     {
                               if(a[i]==)
                                         break;
                               i++;
                     }
                     sort(a,a+i);
                     int count = ;
                     for(int j = i-;j>=;j--)
                     {
                               if(bs(a,a[j]*,i)!=-)
                               {
                                         count++;
                               }
                     }
                     cout<<count<<endl;

           }
 }