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=200010;
int n,l[MAXN],r[MAXN];
int main () {
	scanf("%d",&n);
	for (int i=1;i<=n;i++) {
		scanf("%d%d",&l[i],&r[i]);
	}
	sort(l+1,l+n+1);
	sort(r+1,r+n+1);
	if (n&1) {
		printf("%d\n",r[n/2+1]-l[n/2+1]+1);
	} else {
		printf("%d\n",r[n/2]+r[n/2+1]-l[n/2]-l[n/2+1]+1);
	}
	return 0;
}