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;
typedef long long ll;
#define rep(i, n) for (ll i = 0; i < (ll)(n); i++)
ll ans = 0;

int main()
{
ll n ;
cin >> n ;
vector<ll> a(n,0);
vector<ll> b(n,0);
rep(i,n){
  cin >> a[i] >> b[i];
}
sort(a.begin(),a.end());
sort(b.begin(),b.end());
if(n%2){
  ans=b[n/2]-a[n/2]+1;
}
else ans=b[n/2]+b[n/2-1]-a[n/2]-a[n/2-1]+1;
cout << ans << endl;
return 0;
}