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 N = 2e5 + 5;
int n,a[N],b[N];

int main(){
	scanf("%d",&n);
	for(int i = 1;i<=n;i++) scanf("%d%d",&a[i],&b[i]);
	if(n%2){
		sort(a+1,a+n+1);
		sort(b+1,b+n+1);
		printf("%d",b[n/2+1]-a[n/2+1]+1);
	}else{
		sort(a+1,a+n+1);
		sort(b+1,b+n+1);
		printf("%d",(b[n/2]+b[n/2+1])-(a[n/2]+a[n/2+1])+1);
	}
	return 0;
}