#include<iostream>
#include<math.h>
#include<algorithm>
#include<stdint.h>
#include<vector>
#include<deque>
#include<stack>
#include<functional>
#include<string>
#include<numeric>
#include<cstring>
#include<random>
#include<array>
#include<fstream>
#include<iomanip>
#include<list>
#include<set>
#include<map>
#include<unordered_map>
#include<unordered_set>
#include<bitset>
#include<queue>

/*
#include<boost/multiprecision/cpp_int.hpp>
using namespace boost::multiprecision;
*/

using namespace std;

using ll = long long;
using ull = unsigned long long;

#define REP(i,a,b) for(ll i = a; i < b; ++i)
#define PRI(s) std::cout << s << endl
#define PRIF(v, n) printf("%."#n"f\n", (double)v)

template<typename A, typename B>void mins(A& a, const B& b) { a = min(a, (A)b); };
template<typename A, typename B>void maxs(A& a, const B& b) { a = max(a, (A)b); };


int main() {

	ll N; cin >> N;
	vector<ll> A(N);
	REP(i, 0, N) cin >> A[i];
	vector<ll> B(N);
	REP(i, 0, N) cin >> B[i];

	ll ans = 1e18;
	REP(s, 0, N) {
		auto cmp = [](auto a, auto b) {
			if (a.first == b.first) return a.second > b.second; 
			return a.first > b.first;
		};
		priority_queue<pair<ll, ll>, vector< pair<ll, ll>>, decltype(cmp)> q{ cmp };

		REP(i, 0, N) q.push({ A[i], 0 });
		REP(i, 0, N) {
			ll ind = (i + s) % N;
			auto p = q.top();
			q.pop();

			p.first += B[ind] / 2;
			p.second++;

			q.push(p);
		}

		ll tmp = 0;
		while (!q.empty()) maxs(tmp, q.top().second),  q.pop();
		
		mins(ans, tmp);
	}
	PRI(ans);
	return 0;
}