There are N integers X_1, X_2, \cdots, X_N, and we know that A_i \leq X_i \leq B_i. Find the number of different values that the median of X_1, X_2, \cdots, X_N can take.

Constraints

* 2 \leq N \leq 2 \times 10^5
* 1 \leq A_i \leq B_i \leq 10^9
* All values in input are integers.

Input

Input is given from Standard Input in the following format:


N
A_1 B_1
A_2 B_2
:
A_N B_N


Output

Print the answer.

Examples

Input

2
1 2
2 3


Output

3


Input

3
100 100
10 10000
1 1000000000


Output

9991
import java.util.*;

public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int[] a = new int[n];
    int[] b = new int[n];
    for(int i = 0; i < n; i++) {
      a[i] = sc.nextInt();
      b[i] = sc.nextInt();
    }
    Arrays.sort(a);
    Arrays.sort(b);
    int A = a[n / 2];
    int B = b[n / 2];
    int ans = B - A + 1;
    if((n % 2) == 0) {
      int aa = (a[n / 2] + a[(n / 2) - 1]);
      int bb = (b[n / 2] + b[(n / 2) - 1]);
      ans = (bb - aa + 1);
    }
    System.out.println(ans);
  }
}