#include<iostream>
#include<vector>
#include<string>
#include<algorithm>	
#include<map>
#include<set>
#include<utility>
#include<cmath>
#include<cstring>
#include<queue>
#include<stack>
#include<cstdio>
#include<sstream>
#include<iomanip>
#include<assert.h>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define pb push_back
#define mt make_tuple
#define all(in) in.begin(),in.end()
#define shosu(x) fixed<<setprecision(x)
using namespace std;
//kaewasuretyuui
typedef long long ll;
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vp;
typedef vector<vp> vvp;
typedef vector<string> vs;
typedef vector<double> vd;
typedef tuple<int,int,int> tp;
typedef vector<tp> vt;
typedef vector<vd> vvd;
typedef pair<int,pii> pip;
typedef vector<pip>vip;
const double PI=acos(-1);
const double EPS=1e-7;
const int inf=1e8;
const ll INF=1e16;
int dx[]={0,1,0,-1};
int dy[]={1,0,-1,0};
int main(){
	int n;
	cin>>n;
	vi a(n),b(n);
	rep(i,n)cin>>a[i];
	rep(i,n)cin>>b[i];
	int out=inf;
	rep(i,n){
		int ma=0;
		priority_queue<pii>que;
		rep(j,n)que.push(pii(-a[j],0));
		rep(j,n){
			int t=b[(i+j)%n]/2;
			pii p=que.top();
			que.pop();
			p.first-=t;
			p.second--;
			ma=max(ma,-p.second);
			que.push(p);
		}
		out=min(out,ma);
	}
	cout<<out<<endl;
}