#include <bits/stdc++.h>
using namespace std;
FILE *in, *out;
const int NMAX = 30005;
const double eps = 0.001;
int c[NMAX], t[NMAX], n, l, u;
double s[NMAX];
bool ok(double val) {
deque<int> d;
d.push_front(1);
for(int i = 1;i <= n;i ++)
s[i] = 1.0 * c[i] - val * 1.0 * t[i];
for(int i = l;i <= n; i ++) {
if(!d.empty() && d.front() == i - u - 1)
d.pop_front();
while(!d.empty() && s[d.back()] > s[i - l + 1])
d.pop_back();
d.push_back(i - l + 1);
if(s[i] - s[d.front()] > 0)
return 1;
}
return 0;
}
int main() {
in = fopen("secv3.in", "r");
out = fopen("secv3.out", "w");
fscanf(in, "%d %d %d", &n, &l, &u);
for(int i = 1; i <= n; i ++) {
fscanf(in, "%d", &c[i]);
c[i] += c[i-1];
}
for(int i = 1; i <= n; i ++) {
fscanf(in, "%d", &t[i]);
t[i] += t[i-1];
}
double ans = 0.0;
for(double step = (1 << 9); step > eps; step /= 2.0)
if(ok((ans + step)))
ans += step;
fprintf(out,"%lf", ans);
return 0;
}