1 #include <iostream>
2 #include <algorithm>
3 #include <cstring>
4 #include <cstdio>
5 #include <bitset>
6 #include <vector>
7 #include <queue>
8 #include <stack>
9 #include <cmath>
10 #include <list>
11 #include <set>
12 #include <map>
13 #define rep(i,a,b) for(int i = a;i <= b;++ i)
14 #define per(i,a,b) for(int i = a;i >= b;-- i)
15 #define mem(a,b) memset((a),(b),sizeof((a)))
16 #define FIN freopen("in.txt","r",stdin)
17 #define FOUT freopen("out.txt","w",stdout)
18 #define IO ios_base::sync_with_stdio(0),cin.tie(0)
19 #define mid ((l+r)>>1)
20 #define ls (id<<1)
21 #define rs ((id<<1)|1)
22 #define INF 0x3f3f3f3f
23 using namespace std;
24 typedef long long LL;
25 typedef pair<int, int> PIR;
26 const int N = 6e4+5;
27
28 int n;
29 double x[N], v[N];
30 bool judge(double md){
31 double l = 0, r = 1e9*1.0;
32 rep (i, 1, n) {
33 double ll = x[i]-v[i]*md, rr = x[i]+v[i]*md;
34 if(ll < l && ll > r && rr < l && rr > r) return false;
35 l = max(ll, l);
36 r = min(rr, r);
37 if(l > r) return false;
38 }
39 return true;
40 }
41 int main()
42 {
43 //FIN;
44 while (scanf("%d", &n) != EOF) {
45 rep (i, 1, n) scanf("%lf", &x[i]);
46 rep (i, 1, n) scanf("%lf", &v[i]);
47 double low = 0, high = 1e9*1.0, ans = 0;
48 rep (i, 1, 300) {
49 double md = (low+high)/2;
50 if(judge(md)) { high = md-1; ans = md; }
51 else low = md+1;
52 }
53 printf("%.6lf\n", ans);
54 }
55 return 0;
56 }
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