#include<stdio.h>
int N,L,U,X,i,j,G[30002],P,aux,g,gi,gn;
double c[30002],t[30002],d[30002],sol,sc,dc;
void read(),solve();
int main()
{
	read();
	solve();
	return 0;
}
void read()
{
	freopen("secv3.in","r",stdin);
	freopen("secv3.out","w",stdout);
    scanf("%d%d%d",&N,&L,&U);
    for(i=1;i<=N;i++)scanf("%lf",&c[i]);
    for(i=1;i<=N;i++){scanf("%lf",&t[i]);d[i]=c[i]/t[i];c[i]+=c[i-1];t[i]+=t[i-1];}
}
void solve()
{
	if(U>=2*L)U=2*L-1;
    for(P=L;P<=N;P++)
	{
		sc=(c[P]-c[P-L])/(t[P]-t[P-L]);
		sol=(sc>sol)?sc:sol;
	}
	for(P=L+1;P<=N;P++)
		G[++g]=P;
	for(X=L+1;X<=U;X++)
	{
		gi=1;if(G[1]==X-1)gi=2;
		gn=0;sc=0;
		for(;gi<=g;gi++)
		{
			P=G[gi];
			if(d[P]<sol)continue;
			dc=(c[P]-c[P-X])/(t[P]-t[P-X]);
			sc=sc>dc?sc:dc;
			G[++gn]=P;
		}
		if(sc<sol&&N>20000)break;
		g=gn;if(!gn)break;
		sol=sol>sc?sol:sc;
	}
	printf("%.2lf",sol);
}