#include <cstdio>
#include <cstdlib>
#include <deque>
#include <algorithm>
using namespace std;

const int NMAX = 30010;

int N, L, U, Cost[NMAX], Time[NMAX];

bool Check(double X)
{
    double V[NMAX], S[NMAX];

    S[0] = 0;
    for(int i = 1; i <= N; ++ i)
        V[i] = Cost[i] - X * Time[i], S[i] = S[i - 1] + V[i];

    deque<int> D;

    for(int i = 1; i <= N; ++ i)
    {
        while(!D.empty() && S[D.back()] >= S[i]) D.pop_back();
        if(i - L >= 0) D.push_back(i - L);
        while(!D.empty() && D.front() <= i - U) D.pop_front();
        if(!D.empty() && S[i] >= S[D.front()])
            return 1;
    }
    return 0;
}

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

    scanf("%i %i %i", &N, &L, &U);
    for(int i = 1; i <= N; ++ i) scanf("%i", &Cost[i]);
    for(int i = 1; i <= N; ++ i) scanf("%i", &Time[i]);

    double Left = 0, Right = 30000, Mid, Ans;
    for(int Steps = 0; Steps <= 500; Steps ++)
    {
        Mid = (Left + Right) / 2;
        if(Check(Mid)) Ans = Mid, Left = Mid;
        else Right = Mid;
    }

    printf("%.2lf\n", Ans);
    return 0;
}