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[] A=new int[N];
    int[] B=new int[N];
    for(int i=0;i<N;i++){
      A[i]=sc.nextInt();
      B[i]=sc.nextInt();
    }
    
    Arrays.sort(A);
    Arrays.sort(B);
    
    int min=0;
    int max=0;
    if(N%2==0){
      min=A[N/2-1]+A[N/2];
      max=B[N/2-1]+B[N/2];
    }else{
      min=A[(N-1)/2];
      max=B[(N-1)/2];
    }
      
     
    System.out.println(max-min+1);
  }
}