const

  mm=<<;

  maxnumber=;

  maxn=;

var

  left,right,fix,key:array[..maxn]of longint;

  t,n,ans,i,j,k,l,tot:longint;

function min(x,y:longint):longint;

begin

  if x<y then exit(x);

  exit(y);

end;

function max(x,y:longint):longint;

begin

  if x<y then exit(y);

  exit(x);

end;

procedure lt(var t:longint);

var

  k:longint;

begin

  k:=right[t];

  right[t]:=left[k];

  left[k]:=t;

  t:=k;

end;

procedure rt(var t:longint);

var

  k:longint;

begin

  k:=left[t];

  left[t]:=right[k];

  right[k]:=t;

  t:=k;

end;

procedure insert(var t:longint;v:longint);

begin

  if t= then begin

    inc(tot);

    t:=tot;

    key[t]:=v;

    fix[t]:=random(maxnumber)+;

    left[t]:=;

    right[t]:=;

    exit;

  end;

  if v<=key[t] then begin

    insert(left[t],v);

    if fix[left[t]]>fix[t] then rt(t);

  end

  else begin

    insert(right[t],v);

    if fix[right[t]]>fix[t] then lt(t);

  end;

end;

function pred(t,v:longint):longint;

begin

  if t= then exit(-mm);

  if v=key[t] then exit(v);

  if v<key[t] then exit(pred(left[t],v))

  else

    exit(max(key[t],pred(right[t],v)));

end;

function succ(t,v:longint):longint;

begin

  if t= then exit(mm);

  if v=key[t] then exit(v);

  if v<key[t] then exit(min(key[t],succ(left[t],v)))

  else

    exit(succ(right[t],v));

end;

begin

  t:=;

  readln(n);

  read(j);

  insert(t,j);

  ans:=j;

  for i:= to n do begin

    read(j);

    k:=pred(t,j);

    l:=succ(t,j);

   // writeln(j,' ',k,' ',l);

    if j-k<l-j then ans:=ans+j-k

      else ans:=ans+l-j;

    insert(t,j);

  end;

  writeln(ans);

  readln;

  readln;

end.