uses crt;
var kt:integer; s1,s2,s3:string;
begin
clrscr;
   write('Nhap mat khau lan 1: ');readln(s1);
   write('Nhap lai mat khau lan 2: ');readln(s2);
   if s1<>s2 then
      begin
         write('Nhap lai mat khau lan 3: ');readln(s3);
         write('Ban co muon doi mat khau tiep tuc? (1:Co;  2:Khong): ');readln(kt);
         if kt=1 then 
            begin
               write('Nhap mat khau lan 1: ');readln(s1);
               write('Nhap lai mat khau lan 2: ');readln(s2); 
            end;
      end;
   writeln('Ket thuc');
readln
end.