var s: string;
ch: char;
i,j,k: integer;
begin
write('строка: '); readln(s);
k:=1; j:=2;
i:=1; ch:=s[i];
repeat
while j<=length(s) do <br> begin
if ch=s[j] then
begin
k:=k+1;
delete(s,j,1);
j:=j-1;
end;
j:=j+1;
end;
if k=1 then write(ch,' ');
i:=i+1; k:=1; ch:=s[i];
if i=length(s) then writeln(ch);
j:=i+1;
until j>length(s);
end.