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.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

public class Main {
    public static void main(String args[]) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n =Integer.parseInt(br.readLine());
        List<Integer> a = new ArrayList<>();
        List<Integer> b = new ArrayList<>();
        for(int i=0;i<n;i++){
            String[] tokens = br.readLine().split(" ");
            a.add(Integer.parseInt(tokens[0]));
            b.add(Integer.parseInt(tokens[1]));
        }
        int medA = median(a);
        int medB = median(b);
        System.out.println(Math.abs(medB-medA)+1);
    }

    public static int median(List<Integer> list){
        Collections.sort(list);
        if(list.size()%2==1){
            return list.get(list.size()/2);
        }else {
            return list.get(list.size()/2)  + list.get(list.size()/2 -1);
        }
    }



}