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.math.BigDecimal;
import java.math.BigInteger;
import java.util.*;

public class Main {
    static Input in = new Input(System.in);
    static PrintWriter out = new PrintWriter(System.out);

    public static void main(String[] args) {
        int N = in.nextInt();
        int[] A = new int[N];
        int[] B = new int[N];
        for (int i = 0; i < N; i++) {
            A[i] = in.nextInt();
            B[i] = in.nextInt();
        }
        Arrays.sort(A);
        Arrays.sort(B);
        if (N % 2 == 0) {
            out.println(B[N/2-1] + B[N/2] - A[N/2-1] - A[N/2] + 1);
        } else {
            out.println(B[N/2] - A[N/2] + 1);
        }

        out.flush();
    }

    static class Input {
        private BufferedReader br;
        private String[] buff;
        private int index = 0;

        Input(InputStream is) {
            br = new BufferedReader(new InputStreamReader(is));
        }
        String nextLine() {
            try {
                return br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return null;
        }
        String next() {
            while (buff == null || index >= buff.length) {
                buff = nextLine().split(" ");
                index = 0;
            }
            return buff[index++];
        }
        byte nextByte() {
            return Byte.parseByte(next());
        }
        short nextShort() {
            return Short.parseShort(next());
        }
        int nextInt() {
            return Integer.parseInt(next());
        }
        long nextLong() {
            return Long.parseLong(next());
        }
        float nextFloat() {
            return Float.parseFloat(next());
        }
        double nextDouble() {
            return Double.parseDouble(next());
        }
        BigInteger nextBigInteger() {
            return new BigInteger(next());
        }
        BigDecimal nextBigDecimal() {
            return new BigDecimal(next());
        }
    }
}

