HYSBZ_1588_set

#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
#include<set>
using namespace std;

set<int> s;
set<int>::iterator it;

int main()
{
    int temp,n;
    scanf("%d",&n);
    scanf("%d",&temp);
    int sum = temp;
    s.insert(temp);
    for(int i = 2;i <= n;i++)
    {
        scanf("%d",&temp);
        it = s.lower_bound(temp);
        if(it == s.begin()) sum += *it-temp;
        else if(it == s.end())  sum += temp-*(--it);
        else
        {
            int a = *it-temp,b = temp-*(--it);
            sum += min(a,b);
        }
        s.insert(temp);
    }
    printf("%d\n",sum);
    return 0;
}