#include<fstream>
#include<deque>
#include<iomanip>
using namespace std;
ifstream fin("secv3.in");
ofstream fout("secv3.out");

const int NMax=30000;
double sumA[NMax+5],sumB[NMax+5];
int a[NMax+5],b[NMax+5];
deque<int>dq;

int main(){
    int n,L,U;
    fin>>n>>L>>U;
    for(int i=1;i<=n;i++){
        fin>>a[i];
        sumA[i]=sumA[i-1]+a[i];
    }
    for(int i=1;i<=n;i++){
        fin>>b[i];
        sumB[i]=sumB[i-1]+b[i];
    }
    double Max=0;
    for(int i=L;i<=n;i++){
        while(!dq.empty()&&dq.front()<i-U) dq.pop_front();
        while(!dq.empty()&&(sumA[dq.back()]-sumB[dq.back()]*Max)>(sumA[i-L]-sumB[i-L]*Max)) dq.pop_back();
        dq.push_back(i-L);
        double raport=(sumA[i]-sumA[dq.front()])/(sumB[i]-sumB[dq.front()]);
        if(raport>Max) Max=raport;
    }
    fout<<fixed<<setprecision(2)<<Max;
    return 0;
}