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 int long long
const int MAX = 510000;
const int MOD = 1000000007;


     signed main(){
         

int n;
cin>>n;
int a[n],b[n];
for(int i=0;i<n;i++)cin>>a[i]>>b[i];
sort(a,a+n);sort(b,b+n);
if(n%2){
     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;

}









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