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;
using ll = long long;

const int MAX_N = 2e5+10;
int N;
ll A[MAX_N],B[MAX_N];

void solve()
{
	sort(A,A+N);
	sort(B,B+N);
	if(N&1){
		cout<<B[N/2]-A[N/2]+1<<'\n';
	}else{
		ll lo=A[N/2-1]+A[N/2];
		ll hi=B[N/2-1]+B[N/2];
		cout<<hi-lo+1<<'\n';
	}
}

int main()
{
	ios::sync_with_stdio(false);
	cin >> N;
	for(int i=0;i<N;++i) cin >> A[i] >> B[i];
	solve();
	return 0;
}