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>
#define int long long
using namespace std;

int n,ans;
int a[200005],b[200005];

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