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{
	public static void main(String[] args) throws IOException{
		BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
		int N = Integer.parseInt(reader.readLine());
		int[] As = new int[N];
		int[] Bs = new int[N];
		for(int i = 0;i<N;++i){
			String[] lo = reader.readLine().split(" ");
			int A = Integer.parseInt(lo[0]);
			int B = Integer.parseInt(lo[1]);
			As[i] = A;
			Bs[i] = B;
		}
		Arrays.sort(As);
		Arrays.sort(Bs);
		int max = N%2==0? Bs[N/2 -1]+Bs[N/2] : 2*Bs[N/2];
		int min = N%2==0? As[N/2 - 1] + As[N/2]:2*As[N/2];
		int res = N%2==0? 1 + (max-min):1+(max-min)/2; 
		System.out.println(res);
	}
}
