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
#include <bits/stdc++.h>
using namespace std;

int main() {
  int N;
  cin>>N;
  vector<int> a(N);
  vector<int> z(N);
  for(int i=0;i<N;i++){
    cin>>a.at(i)>>z.at(i);
  }
  sort(a.begin(), a.end());
  sort(z.begin(), z.end());
  if(N%2==1){
    cout<<1+z.at(N/2)-a.at(N/2)<<endl;
  }
  else{
    cout<<1+z.at(N/2)-a.at(N/2)+z.at(N/2-1)-a.at(N/2-1)<<endl;
  }
}