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> 
#define ll long long
using namespace std; 

/* Driver code */
int main()  
{  
    ll n, i, z;
    cin>>n;
    ll A[200000], B[200000];
    for(i=0; i<n; i++)
    cin>>A[i]>>B[i];
    sort(A, A+n);
    sort(B, B+n);
    if(n%2==1)
    {
        z = B[n/2]-A[n/2]+1;
    }
    else
    {
        z = B[n/2]+B[n/2-1]-A[n/2]-A[n/2-1]+1;
    }
    cout<<z;
    return 0;  
}  