var s:string; e:set of char; i:integer;
begin
readln(s);
e:=[];
for i:=1 to length(s) do
if s[i] in ['0'..'9','-','+','*','/']
then e:=e+[s[i]];
for i:=0 to 255 do if chr(i) in e then write(chr(i));
readln;
end.
var s:string; e:set of char; i:integer;
begin
readln(s);
e:=[];
for i:=1 to length(s) do
if s[i] in ['0'..'9','-','+','*','/']
then e:=e+[s[i]];
for i:=0 to 255 do if chr(i) in e then write(chr(i));
readln;
end.