2015湘潭市第七届大学生程序设计竞赛 —— Fraction

题目大意：

　　小数化分数，但是分母限制在[1,1000],很明显的枚举，但是在赛场上的时候傻逼了，无论怎么枚举，怎么二分就是wa，wa到死···········。

（ps：我要给出题人寄刀片~~~~），这个题目需要注意的是有可能输出0/1.

 #include <cmath>
 #include <cstdio>
 #include <cstring>
 #include <iostream>
 #include <algorithm>
 using namespace std;
 const int maxn = ;

 struct node
 {
     int x, y;
 };
 node stu[maxn];
 bool cmp (node a, node b)
 {
     return a.x*1.0/a.y < b.x*1.0/b.y ? true : false;
 }

 int gcd (int a, int b)
 {
     return a%b==?b:gcd(b, a%b);
 }

 int Bin_Sreach(double n, int low, int high)
 {
     while (low <= high)
     {
         int mid = (low + high) / ;
         double num = stu[mid].x * 1.0 / stu[mid].y;
         if (num < n)
             low = mid;
         if (num > n)
             high = mid;
         if (high - low == )
             break;
     }
     double num1 = stu[low].x*1.0 / stu[low].y;
     double num2 = stu[high].x*1.0 / stu[high].y;
     if (fabs(n - num1) > fabs(n - num2))
         return high;
     return low;
 }
 int main ()
 {
     int t, k = ;

     stu[].y = ;
     for (int i=; i<=; i++)
         for (int j=i; j<=; j++)
         {
             if (gcd(j, i) == )
             {
                 stu[k].x = i;
                 stu[k++].y = j;
             }
         }
         sort (stu, stu+k, cmp);

         scanf ("%d", &t);
         while (t --)
         {
             double n;
             scanf ("%lf", &n);
             int p = Bin_Sreach(n, , k-);
             printf ("%d/%d\n", stu[p].x, stu[p].y);
         }
         return ;
 }