uses crt;
var i:integer;
s1,s2:string[100];
begin
clrscr;
writeln('Nhap xau khong qua 100 ki tu:');readln(s1);
s2:='';
for i := 1 to length(s1) do
if (ord(s1[i]) in ['32'..'64']) or (ord(s1[i]) in ['91'..'96']) or (ord(s1[i]) in ['123'..'126']) then s2:=s2+s1[i];
writeln('Xau da xoa tat ca cac ki tu chu cai:');writeln(s2);
readln;
end.