program p1014;var c2,c5,n,i:longint; procedure main(w:longint); begin while w mod 2=0 do begin w:=w div 2;inc(c2);end; while w mod 5=0 do begin w:=w div 5;inc(c5);end; end;begin repeat readln(n); c2:=0;c5:=0; for i:=1 to n do main(i); if c2>c5 then writeln(c5) else writeln(c2); until seekeof;end.