#include <bits/stdc++.h>
using namespace std;

int n, l, u;
vector<double> c, t, sp;

bool check(double x)
{
    sp[0] = 0;
    for(int i = 1; i <= n; ++i)
        sp[i] = sp[i-1] + c[i] - x * t[i];

    double maxx = 0;
    deque<int> dq;
    for(int i = l; i <= n; ++i) {
        while(!dq.empty() && dq.front() < i - u)
            dq.pop_front();
        while(!dq.empty() && sp[i - l] <= sp[dq.back()])
            dq.pop_back();
        dq.push_back(i - l);
        maxx = max(maxx, sp[i] - sp[dq.front()]);
    }

    return maxx > 0;
}

signed main()
{
#ifndef LOCAL
    cin.tie(nullptr)->sync_with_stdio(false);
    freopen("secv3.in", "r", stdin);
    freopen("secv3.out", "w", stdout);
#endif

    cin >> n >> l >> u;

    c.resize(n + 2); t.resize(n + 2); sp.resize(n + 2);

    for(int i = 1; i <= n; ++i)
        cin >> c[i];
    for(int i = 1; i <= n; ++i)
        cin >> t[i];

    double st = 0, dr = 1000;
    int it = 0;
    for(; it < 60; ++it) {
        double mij = (st + dr) / 2;
        if(check(mij))
            st = mij;
        else
            dr = mij;
    }

    cout << fixed << setprecision(2) << st;
}