二分搜索 POJ 1064 Cable master

题目传送门

 /*
     题意：n条绳子问切割k条长度相等的最长长度
     二分搜索：搜索长度，判断能否有k条长度相等的绳子
 */
 #include <cstdio>
 #include <algorithm>
 #include <cstring>
 #include <cmath>
 using namespace std;

 const int MAXN = 1e4 + ;
 const int INF = 0x3f3f3f3f;
 double w[MAXN];
 int n, k;

 int check(double len)   {
     int ret = ;
     for (int i=; i<=n; ++i)    {
         ret += (int) (w[i] / len);
     }
     return ret;
 }

 int main(void)  {       //POJ 1064 Cable master
     //freopen ("POJ_1064.in", "r", stdin);

     while (scanf ("%d%d", &n, &k) == ) {
         for (int i=; i<=n; ++i)    {
             scanf ("%lf", &w[i]);
         }
         double l = , r = 1e9;
         for (int i=; i<=; ++i)  {
             double mid = (l + r) / ;
             if (check (mid) >= k)   l = mid;
             else    r = mid;
         }
         printf ("%.2f\n", floor (l * ) / );
     }

     return ;
 }