#include <bits/stdc++.h>
using namespace std;
const int buff = 1e4;
long long A[100008], B[100008];
signed main() {
ios_base::sync_with_stdio(0);
cin.tie(0); cout.tie(0);
int n; double x; cin >> n;
for (int i = 1; i <= n; ++i) cin >> x, A[i] = round(x * buff);
for (int i = 1; i <= n; ++i) cin >> x, B[i] = round(x * buff);
sort(A + 1, A + n + 1, greater<long long>()); sort(B + 1, B + n + 1, greater<long long>());
partial_sum(A, A + n + 1, A); partial_sum(B, B + n + 1, B);
int j; long double ans = 0;
for (int i = 1; i <= n && A[i] <= B[n]; ++i) { // A[i] < B[j]
j = lower_bound(B + 1, B + n + 1, A[i]) - B;
ans = max(ans, (long double) (A[i] * 1.0) / buff - i - j);
}
for (int i = 1; i <= n && B[i] <= A[n]; ++i) { // B[i] < A[j]
j = lower_bound(A + 1, A + n + 1, B[i]) - A;
ans = max(ans, (long double) (B[i] * 1.0) / buff - i - j);
}
cout << fixed << setprecision(8) << ans;
}
