uses crt;
var  p,i,nr,aux:integer; f:text; ok:boolean;
begin
     clrscr;
     assign(f,'fact.in');
     reset(f);
     read(f,p);
     close(f);
     assign(f,'fact.out');
     rewrite(f);
     i:=0; nr:=0;
     repeat
     i:=i+5;
     aux:=i;
     while aux mod 5=0 do
     begin
     aux:=aux div 5;
     nr:=nr+1;
     end;
     IF nr=p then
     begin
     write(f,i);
     break;
     ok:=true;
     end;
     until ok;
     close(f);


     readln;
end.