#include <bits/stdc++.h>



#define NMAX 30000
#define LOG 19
#define ll long long int
#define MOD 1000000007
#define EPS 100
using namespace std;



ifstream fin("secv3.in");
ofstream fout("secv3.out");


int v[NMAX+1], t[NMAX+1];

int n,l,u;
bool check(int S)
{
    deque<int> dq;
    vector<ll> d(n+1,0);
    for(int i=1;i<=n;i++)
    {
        d[i] = v[i]*EPS - t[i] * S;
        d[i] += d[i-1];
    }

    bool ok=0;
    for(int i=l;i<=n;i++)
    {
        while(!dq.empty() && d[dq.back()] >= d[i])
        {
            dq.pop_back();
        }
        dq.push_back(i-l);
        if(!dq.empty() && dq.front() < i-u)
        {
            dq.pop_front();
        }
        ok |= d[i] - d[dq.front()] >= 0;
    }
    return ok;
}
int main()
{
    fin >> n >> l >> u;
    for(int i=1;i<=n;i++)
    {
        fin >> v[i];
    }
    for(int i=1;i<=n;i++)
    {
        fin >> t[i];
    }

    int st=0,dr=1000*EPS;
    while(st<=dr)
    {
        int m = (st+dr)/2;
        if(check(m))
        {
            st=m+1;
        }
        else
        {
            dr=m-1;
        }
    }
    fout << (double)dr/EPS;
}