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;

int main(){
    long N;
    cin >> N;
    long A[N], B[N];
    for(long 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;
    }else{
        cout << B[N / 2] + B[(N / 2) - 1] - A[N / 2] - A[(N / 2) - 1] + 1 << endl;
    }
    return 0;
}