program bai17;

uses crt;

var i,n,a:integer;

begin

clrscr;

write('Nhap so tien hien co: ');   readln(a);

write('Nhap so tien can co de mua tro choi: ');   readln(n);

if a>=n then write('Khong can lam') else

for i:=1 to n do

 begin

  a:=a*2;

  if a>=n then

    begin

      write('Can ',i,' ngay');

      break;

    end;

 end;

readln

end.

program bai18;

uses crt;

var n,i:integer;

       t:longint;

begin

clrscr;

write('Nhap n: ');   readln(n);

t:=0;

for i:=1 to n do

 if n mod i=0 then t:=t+i;

write('Tong cac uoc duong cua ',n,' la: ',t);

readln

end.

program bai18;

uses crt;

var n,i:integer;

begin

clrscr;

write('Nhap n: ');  readln(n);

if n mod 2=1 then write('Khong co')

 else 

 begin

  writeln('Cac uoc chan cua n la:');

  for i:=2 to n do

   if (n mod i=0) and (i mod 2=0) then writeln(i);

  end.

readln

end.

17)

uses crt;
var a,n,k:longint;
begin
clrscr;
   write('a,n=');readln(a,n);
   while a<n do begin inc(k); a:=a*2; end;
   writeln('Can ',k,' ngay');
readln
end.

19)

uses crt;
var n,i:longint;
begin
clrscr;
   write('n=');readln(n);
   while i<n do begin inc(i); if (i mod 2=0)and(n mod i=0) then writeln(i); end;
readln
end.