#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
	cin.tie(0);
	ios::sync_with_stdio(false);
	int n;
	cin >> n;
	vector<int> a(n), b(n);
	for (int i = 0; i < n; i++) {
		cin >> a[i] >> b[i];
		b[i] -= a[i];
	}

	const int INF = 100000;
	vector< vector<int> > dp(1 << n, vector<int>(n, INF));
	for (int i = 0; i < n; i++) dp[1 << i][i] = 0;

	for (int i = 0; i + 1 < (1 << n); i++) {
		for (int j = 0; j < n; j++) {
			if (!(i & (1 << j))) continue;
			for (int k = 0; k < n; k++) {
				if (i & (1 << k)) continue;
				dp[i | (1 << k)][k] = min(dp[i | (1 << k)][k], max(dp[i][j], b[j] + a[k]));
			}
		}
	}

	int ans = INF;
	for (int i = 0; i < n; i++) ans = min(ans, dp[(1 << n) - 1][i]);
	cout << ans << endl;
	return 0;
}