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

long n;
long a[200000];
long b[200000];
int main() {
  cin >> n;
  for (int i = 0; i < n; ++i) cin >> a[i] >> b[i];
  sort(a, a + n);
  sort(b, b + n);
  
  if (n % 2 == 1) {
    cout << b[n / 2] - a[n / 2] + 1 << endl;
  } else {
    cout << (b[n / 2 - 1] + b[n / 2]) - (a[n / 2 - 1] + a[n / 2]) + 1 << endl;
  }
}