Toi su dung sma va hma . Toi von k biet ve lap trinh nen toi chi co the viet ra nhung chien luoc don gian va toi cung thich su don gian . Toi hi vong lan nay chien luoc cua toi se mang ve nhieu loi nhuan ...Toi cam thay no co ve hieu qua , uhm maybe