#include<algorithm>
using namespace std;

#define DIM 30001

int n,l,u;
double sol;

struct gigel{
	int c,t;};
gigel a[DIM];

void read(){
	int i;

	scanf("%d%d%d",&n,&l,&u);
	for(i=1; i<=n; ++i)
		scanf("%d",&a[i].c);
	for(i=1; i<=n; ++i)
		scanf("%d",&a[i].t);}

void solve(){
    int i,j;

    for(i=1; i<=n; ++i){
        a[i].c+=a[i-1].c;
        a[i].t+=a[i-1].t;}
    for(i=0; i<=n-l; ++i)
        for(j=i+l; j<=i+u; ++j)
			if((double)(a[j].c-a[i].c)/(a[j].t-a[i].t)>sol)
                sol=(double)(a[j].c-a[i].c)/(a[j].t-a[i].t);
    printf("%lf",sol);}

int main(){

    freopen("secv3.in","r",stdin);
    freopen("secv3.out","w",stdout);

	read();
    solve();
    return 0;}