program busses;
var
  fin,fout:text;
  i,j,n:longint;
  a:array[1..10]of longint;
  f:array[0..10000000]of longint;
function min(x,y:longint):longint;
begin
  if x<y then min:=x else min:=y;
end;
begin
  assign(fin,'busses.in'); reset(fin);
  assign(fout,'busses.out'); rewrite(fout);
  for i:=1 to 10 do read(fin,a[i]);
  read(fin,n);
  f[0]:=0;
  for i:=1 to n do f[i]:=a[1]*i;
  for i:=2 to 10 do begin
    for j:=i to n do begin
      f[j]:=min(f[j],f[j-i]+a[i]);
    end;
  end;
  writeln(fout,f[n]);
  close(fin);
  close(fout);
end.