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[] arrA = new int[n];
		int[] arrB = new int[n];
		for (int i = 0; i < n; i++) {
		    arrA[i] = sc.nextInt();
		    arrB[i] = sc.nextInt();
		}
		Arrays.sort(arrA);
		Arrays.sort(arrB);
		int count;
		if (n % 2 == 0) {
		    int left = arrA[(n - 1) / 2] + arrA[(n - 1) / 2 + 1];
		    int right = arrB[(n - 1) / 2] + arrB[(n - 1) / 2 + 1];
		    count = Math.max(right - left + 1, 0);
		} else {
		    int left = arrA[n / 2];
		    int right = arrB[n / 2];
		    count = Math.max(right - left + 1, 0);
		}
	    System.out.println(count);
	}
}
