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