#include <iostream>
using namespace std;
int n, a[20], b[20];

inline int calc(int i, int j) {
    return a[j] + b[i] - a[i];
}

int memo[1<<18][18];

int solve(int s, int i) {
    if (memo[s][i] > 0) return memo[s][i];
    int ans = 1<<30;
    int s1 = s ^ (1<<i);
    if (s1 == 0) ans = 0;
    for (int j = 0; j < n; j++) {
        if (s1 & (1<<j)) {
            ans = min(ans, max(solve(s1, j), calc(j, i)));
        }
    }
    return memo[s][i] = ans;
}

int main () {
    cin >> n;
    for (int i = 0; i < n; i++) cin >> a[i] >> b[i];
    int ans = 1<<30;
    for (int i = 0; i < n; i++) ans = min(ans, solve((1<<n)-1, i));
    cout << ans << endl;
}