program factorial;
var p,s:integer;
    i,j:longint;
    q,l:boolean;
    f1,f2:text;
begin
assign(f1,'fact.in'); reset(f1);
assign(f2,'fact.out'); rewrite(f2);
readln(f1,p);
s:=0;
l:=true;
     i:=1;
while l=true do
  begin
  q:=true;
  j:=i;
  while q=true do
  begin
  if j mod 5=0 then
    begin
    s:=s+1;
    j:=j div 5;
    end
    else
    q:=false;
    end;
    if s=p then
    begin
    l:=false;
    write(f2,i);
    end
    else
    i:=i+1;
  end;
close(f1);
close(f2);
end.