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 minArr[] = new int[n], maxArr[] = new int[n];
		int i = 0;
		while (++i <= n) {
			minArr[i - 1] = sc.nextInt();
			maxArr[i - 1] = sc.nextInt();
		}
		sc.close();
		Arrays.sort(minArr);
		Arrays.sort(maxArr);
		if (n % 2 == 0) {
			int minVal = (minArr[n / 2] + minArr[(n / 2) - 1]);
			int maxVal = maxArr[n / 2] + maxArr[(n / 2) - 1];
			System.out.println(maxVal - minVal + 1);
		} else
			System.out.println(maxArr[n / 2] - minArr[n / 2] + 1);
	}
}
