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.*;
import java.util.*;

public class Main {
    static PrintWriter out = new PrintWriter(System.out);
    static Scanner sc = new Scanner(System.in);
    static BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
    long mod = 1000000000+7;

    public static void main(String[] args) throws IOException {
        Main main = new Main();
        main.solve();
//        out.println(main.solve());
        out.flush();
    }
    void solve() throws IOException {
        int n = sc.nextInt();
        long[] a = new long[n], b = new long[n];
        for(int i=0; i<n; i++){
            a[i] = sc.nextLong(); b[i] = sc.nextLong();
        }
        Arrays.sort(a); Arrays.sort(b);
        long ans;
        if(n%2==1) ans = solveOdd(a,b);
        else ans = solveEven(a,b);
        out.println(ans);
    }
    long solveOdd(long[] a, long[] b){
        int n = a.length;
        long lo = a[n/2], hi = b[n/2];
        return Math.abs(hi-lo)+1;
    }
    long solveEven(long[] a, long[] b){
        int n = a.length;
        long lo = a[n/2-1]+a[n/2], hi = b[n/2-1]+b[n/2];
        return Math.abs(hi-lo)+1;
    }
}