Program mn_11;
var
s: string;
m: set of char;
i: integer;
begin
writeln('Введите текст');
readln(s);
i := 1;
repeat
if s[i] in m then
delete(s, i, 1)
else
begin
include(m, s[i]);
inc(i)
end
until i > length(s);
writeln('Результат:');
writeln(s);
readln
end.