program Tin_hoc;
uses crt;
var i:integer;
s1,s2:string;
begin
clrscr;
writeln('Nhap xau:');readln(s1);
s2:='';
for i:= 1 to length(s1) do if s1[i] in ['0'..'9'] then s2:= s2 + s1[i];
writeln('Xau chi gom so :',s2);
readln;
end.
Nhớ cho mik câu tlhn nha