222×999＋666×667
=222*3*333+666*667
=666*333+666*667
=666*(333+667)
=666*1000
=666000
999×999＋1999
=999^2+1998+1
=999^2+2*999*1+1^2
=(999+1)^2
=1000^2
=1000000