#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
using namespace std;
const double INF = 1e9;
const int maxn = 60000 + 10;
double n, pos[maxn], v[maxn];
bool check(double t) {
double a = pos[0] - v[0] * t, b = pos[0] + v[0] * t;
for (int i = 1; i < n; i++) {
double x = pos[i] - v[i] * t;
double y = pos[i] + v[i] * t;
if (x > b || y < a) return false;
if (a < x) a = x;
if (b > y) b = y;
}
return true;
}
int main()
{
while (scanf("%lf", &n) == 1) {
for (int i = 0; i < n; i++) scanf("%lf", &pos[i]);
for (int i = 0; i < n; i++) scanf("%lf", &v[i]);
double l = 0, r = INF, t, ans = 0;
while (r - l > 1e-7) {
t = (l + r) / 2.0;
if (check(t)) {
r = t;
ans = t;
}
else {
l = t;
}
}
printf("%lf\n", ans);
}
return 0;
}
