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;

#define F first
#define S second


int main(){
	int n; cin >> n;
	vector<int> a(n),b(n);
	for(int i = 0; i < n; ++i){
		cin >> a[i] >> b[i];
	}
	sort(a.begin(),a.end());
	sort(b.begin(),b.end());
	if(n&1){
		cout << b[n/2]  - a[n / 2] + 1;
	}else{
		int bb = b[n / 2] + b[n/2 - 1];
		int aa = a[n / 2] + a[n/2 - 1];
		cout << bb - aa + 1 << "\n";
	}
		
	return 0;
}
