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.Arrays;
import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int n = sc.nextInt();
    int answer = 0;
    int[] array_a = new int[n];
    int[] array_b = new int[n];
    for(int i = 0; i < n; i++){
      array_a[i] = sc.nextInt();
      array_b[i] = sc.nextInt();
    }
    Arrays.sort(array_a);
    Arrays.sort(array_b);
    if(n % 2 == 1){
      answer = array_b[(n - 1) / 2] - array_a[(n - 1) / 2] + 1;
    } else {
      answer = (array_b[(n / 2)] + array_b[(n / 2) - 1]) - (array_a[(n / 2)] + array_a[(n / 2) - 1]) + 1;
    }
    System.out.println(answer);
  }
}