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 {
    private static final int MOD = 1_000_000_007;
    private static final String YES = "Yes";
    private static final String NO = "No";

    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();
        }

        System.out.println(solve3(N, A, B));
    }

    private static long solve3(int N, int[] A, int[] B) {
        long count = 0;

        Arrays.sort(A);
        Arrays.sort(B);

        if (N%2 == 1) {
            count = B[N/2] - A[N/2] + 1;
        } else {
            count = (B[N/2-1] + B[N/2]) - (A[N/2-1] + A[N/2]) + 1;
        }

        return count;
    }

}