#include <stdio.h>
#define N 30001

int cost[N];
int timp[N];
int sc[N];
int st[N];

int main ()
{freopen("secv3.in","r",stdin);
 freopen("secv3.out","w",stdout);
 int n,l,u,i,j,k,it;
 
 double max=0,t;
 scanf("%d %d %d",&n,&l,&u);
 
 for (i=1;i<=n;i++)
 {scanf("%d",&it);
  sc[i]=sc[i-1]+it;
//  printf("%d ",sc[i]);
 }
// printf("\n");
 
 for (i=1;i<=n;i++)
 {scanf("%d",&it);
  st[i]=st[i-1]+it;
//  printf("%d ",st[i]);
 }
//  printf("\n");
 for (i=1;i<=n;i++)
 {for (j=i+l-1;j<=i+u-1;j++)
  {t=((double)sc[j]-sc[i-1])/(st[j]-st[i-1]);
   //printf("%d %d %f\n",i,j,t);
   
   if((t=((double)sc[j]-sc[i-1])/(st[j]-st[i-1]))>max)
   {max=t;
   }
  }
 }
 printf("%lf",max);
 
 return 0;
}