#include<bits/stdc++.h>
using namespace std;
int 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]+b[n/2-1]-a[n/2]-a[n/2-1]+1<<endl;
    return 0;
}