1.
program ct;
uses crt;
var n:integer;
begin
clrscr;
write('nhap mot so:=');readln(n);
if n mod 3=0 then writeln(n,'chi het cho 3') else writeln('khong chia het cho 3);
readln
end.
2.
program ct;
uses crt;
var n:integer;
begin
clrscr;
write('nhap mot so:=');readln(n);
if n mod 2=0 then writeln(n,' la so chan');
if n mod 2<>0 then writeln(n,'la so le');
readln
end.