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;
constexpr ll mod=1000000007;

int N,A[200000],B[200000];

int main(){
	cin>>N;
	for(int i=0;i<N;i++){
		cin>>A[i]>>B[i];
	}
	sort(A,A+N);
	sort(B,B+N);
	if(N&1){
		cout<<B[N/2]-A[N/2]+1<<endl;
	}
	else{
		cout<<(B[N/2-1]+B[N/2]-A[N/2-1]-A[N/2]+1)<<endl;
	}
}
