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 {
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int [] min = new int [n];
        int [] max = new int [n];
        for(int i=0;i<n;i++){min[i] = sc.nextInt();
                             max[i] = sc.nextInt();
                            }
	    Arrays.sort(min);
        Arrays.sort(max);
        if(n%2==0){System.out.println(max[n/2-1]+max[n/2]-min[n/2-1]-min[n/2]+1);}
        else{System.out.println(max[n/2]-min[n/2]+1);}
	}
}