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);
		if(N % 2 == 1)
			System.out.println(B[N/2]-A[N/2]+1);
		else
			System.out.println(B[N/2]+B[N/2-1]-A[N/2]-A[N/2-1]+1);
	}

}