#include <iostream>
#include <vector>
#include <queue>
#include <functional>
#include <limits>

using namespace std;

int main() {
	int n;
	cin >> n;
	vector<int> a(n);
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
	}
	vector<int> b(n);
	for (int i = 0; i < n; ++i) {
		cin >> b[i];
	}
	priority_queue<int, vector<int>, greater<int> > initialUs;
	for (int i = 0; i < n; ++i) {
		initialUs.push((a[i] << 16) | 0x0000);
	}
	int minExperience = numeric_limits<int>::max();
	for (int start = 0; start < n; ++start) {
		priority_queue<int, vector<int>, greater<int> > us(initialUs);
		for (int i = 0; i < n; ++i) {
			int enemy = (start + i) % n;
			int ours = us.top();
			us.pop();
			int level = ours >> 16;
			int experience = ours & 0xFFFF;
			level += b[enemy] / 2;
			++experience;
			us.push((level << 16) | experience);
		}
		int maxExperience = 0;
		while (!us.empty()) {
			int ours = us.top();
			us.pop();
			int experience = ours & 0xFFFF;
			maxExperience = max(maxExperience, experience);
		}
		if (minExperience > maxExperience) {
			minExperience = maxExperience;
		}
	}
	cout << minExperience << endl;
	return 0;
}