#include <bits/stdc++.h> using namespace std; struct breakfast { int place; int time; }a[10010]; bool cmp(breakfast x,breakfast y) { return abs(x.place - x.time) < abs(y.place - y.time); } int main() { int n; cin>>n; for(int i = 0;i < n;i++) { cin>>a[i].place; } for(int i = 0;i < n;i++) { cin>>a[i].time; } sort(a,a + n,cmp); cout<<setprecision(1)<<fixed<<float(a[0].place + a[n - 1].place) / 2<<endl; return 0; }