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;
const int maxn=200005,INF=0x7FFFFFFF;
int n,m,ansL,ansR,a[maxn],b[maxn];
int main()
{
	scanf("%d",&n);
	m=(n+1)>>1;
	for (int i=1;i<=n;i++) scanf("%d%d",&a[i],&b[i]);
	sort(a+1,a+1+n);
	sort(b+1,b+1+n);
	ansL=(n&1)?a[m]:a[m]+a[m+1];
	ansR=(n&1)?b[m]:b[m]+b[m+1];
	//cerr<<">>>>>>"<<ansL<<" "<<ansR<<endl;
	printf("%d\n",ansR-ansL+1);
	return 0;
}
