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 <cstdio>
#include <algorithm>
#define maxn 200010
int a[maxn],b[maxn],n;
using namespace std;
int main(){
	int i,l,r;
	scanf("%d",&n);
	for(i=1;i<=n;i++)scanf("%d%d",&a[i],&b[i]);
	sort(a+1,a+1+n),sort(b+1,b+1+n);
	if(n%2)l=a[(n+1)/2],r=b[(n+1)/2];
	else l=a[n/2]+a[n/2+1],r=b[n/2]+b[n/2+1];
	printf("%d\n",r-l+1);
	return 0;
}