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.io.PrintWriter;
import java.util.*;

public class Main {
    void run() {
        Scanner sc = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);

        int n = sc.nextInt();

        boolean isEven = n % 2 == 0;

        int[] aArr = new int[n];
        int[] bArr = new int[n];

        for (int i = 0; i < n; i++) {
            int a = sc.nextInt();
            int b = sc.nextInt();
            aArr[i] = a;
            bArr[i] = b;
        }

        Arrays.sort(aArr);
        Arrays.sort(bArr);
        debug(aArr);
        int ans;
        double min, max;
        n = n - 1;
        if (isEven) {
            min = (aArr[n / 2] + aArr[(n / 2) + 1]) / (double) 2;
            max = (bArr[n / 2] + bArr[(n / 2) + 1]) / (double) 2;
            ans = (int) ((max - min) * 2) + 1;
        } else {
            min = aArr[n / 2];
            max = bArr[n / 2];
            ans = (int) (max - min) + 1;
        }
        System.out.println(ans);

        // out.println("Hello World");
        out.flush();
    }

    void debug(Object... os) {
        System.err.println(Arrays.deepToString(os));
    }

    public static void main(String[] args) {
        new Main().run();
    }
}
