#include <iostream>
#include <set>

using namespace std;

set<int> q;
int ans;
int n;

int main() {
    cin >> n;
    --n;
    q.insert(-(1 << 31));
    int t ;
    cin >> t;
    q.insert(t);
    ans += t;
    while (n--) {
        cin >> t;
        auto i = q.lower_bound(t);
        int tmp = abs(*i - t);
        --i;
        if(*i != -(1 << 31)) {
            tmp = min(tmp, abs(*i - t));
        }
        q.insert(t);
        ans += tmp;
    }
    cout << ans;
    return 0;
}