#include<bits/stdc++.h>
using namespace std;

//#define int long long

typedef pair<int,int>pint;
typedef vector<int>vint;
typedef vector<pint>vpint;
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define all(v) (v).begin(),(v).end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define reps(i,f,n) for(int i=(f);i<(n);i++)
#define each(it,v) for(__typeof((v).begin()) it=(v).begin();it!=(v).end();it++)
template<class T,class U>void chmin(T &t,U f){if(t>f)t=f;}
template<class T,class U>void chmax(T &t,U f){if(t<f)t=f;}

int N;
int A[1500],B[1500];

signed main(){
    cin>>N;
    rep(i,N)cin>>A[i];
    rep(i,N)cin>>B[i];

    int ans=114514;
    rep(i,N){
        priority_queue<pint,vector<pint>,greater<pint> >que;
        rep(j,N)que.push(pint(A[j],0));
        rep(j,N){
            int k=(i+j)%N;
            pint p=que.top();que.pop();
            p.first+=B[k]/2;
            p.second++;
            que.push(p);
        }
        int tmp=0;
        while(que.size()){
            chmax(tmp,que.top().second);
            que.pop();
        }
        chmin(ans,tmp);
    }
    cout<<ans<<endl;
    return 0;
}