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

signed main () {
    int n;
    cin >> n;
    vector < int > a(n), b(n);
    for (int i = 0; i < n; ++i)
        cin >> a[i] >> b[i];
    sort(a.begin(), a.end());
    sort(b.begin(), b.end());
    if (n & 1)
        cout << b[n / 2] - a[n / 2] + 1 << '\n';
    else
        cout << b[n / 2] + b[n / 2 - 1] - a[n / 2] - a[n / 2 - 1] + 1 << '\n';
}
