#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<math.h>
using namespace std;
#define N (1000000000+7)
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;



int main(void){
    ll ans = 0;
    ll n;
    cin>>n;
    vector<ll>a(2*n);
    for(ll i=0;i<2*n;i++)cin>>a[i];
    ll left = 0,right=2*n-1;
    while(right>left){
        ll tmp1 = a[left]-a[left+1];
        ll tmp2 = a[right]-a[right-1];
        if(tmp1>=tmp2){
            ans+=tmp1;
            left+=2;
        }
        else{
            ans+=tmp2;
            right-=2;
        }
    }
    cout<<ans<<endl;
    //cout<<left<<" "<<right<<endl;
    return 0;
}