POJ1064

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

 int N;
 int K;
 double num[];

 int calc(double len)
 {
     int numK= ;
     for(int i = ; i < N; ++i)
     {
         numK += (int)(num[i] / len);
     }
     return numK;
 }

 double solve()
 {
     double low = ;
     double upper = ;
     int count  = ;
     double mid;
     int numK;
     while(count < )
     {
         mid = (low + upper) / ;
         numK = calc(mid);
         if(numK >= K)
             low = mid;
         else
             upper = mid;
         ++count;
     }
     return mid;
 }

 int main()
 {
     //基于二分法的思想实现
     cin >> N >> K;
     for(int i = ; i < N; ++i)
         cin >> num[i];
         //这里floor很重要
     cout << setiosflags(ios::fixed) << setprecision() << floor(solve()*)/ << endl;
     return ;
 }