CodeForces

#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;}