#include <iostream>

 #include <stdio.h>

 #include <stdlib.h>

 #include <io.h>

 #include <queue>

 #include <map>

 using namespace std;

 struct Tmp

 {

     Tmp()

     {

         l = ;

         r = ;

     }

     int l;

     int r;

 };

 int main()

 {

     //freopen("data.in","r",stdin);

     int n;

     cin>>n;

     map<int,Tmp> mt;

     for(int i = ; i <= n; ++i)

     {

         int k;

         cin>>k;

         mt[k].l = min(mt[k].l, i);

         mt[k].r = max(mt[k].r, i);

     }

     long long ans = n;

     int lastl = ;

     int lastr = ;

     long long LANS = ;

     long long RANS = ;

     for(map<int,Tmp>::iterator it = mt.begin(); it != mt.end(); ++it)

     {

        Tmp tmp = (it->second);

        long long TLN = (tmp.r - tmp.l) + min(abs(tmp.r - lastl) + LANS, abs(tmp.r - lastr) + RANS);

        long long TRN = (tmp.r - tmp.l) + min(abs(tmp.l - lastl) + LANS, abs(tmp.l - lastr) + RANS);

        LANS = TLN;

        RANS = TRN;

        lastl = tmp.l;

        lastr = tmp.r;

     }

     ans += min(LANS, RANS);

     cout<<ans<<endl;

     return ;

 }