POJ 1064 Cable master

 1 #include<iostream>
 2 #include<cstring>
 3 #include<cstdio>
 4 #include<cmath>
 5 using namespace std;
 6 int n,k;
 7 double a[10010];
 8 bool C(double x){
 9     int num=0;
10     for(int i=1;i<=n;i++)
11       num+=(int)(a[i]/x);
12     return num>=k;
13 }
14 void solve(){
15     double l=0,r=10000000;
16     for(int i=0;i<=100;i++){
17         double mid=(l+r)/2;
18         if(C(mid)) l=mid;
19         else r=mid;
20     }
21     printf("%.2lf",floor(r*100)/100);
22 }
23 int main()
24 {
25     scanf("%d%d",&n,&k);
26     for(int i=1;i<=n;i++)
27       scanf("%lf",&a[i]);
28     solve();
29     return 0;
30 }