原式
=666*【1000-333】+222*999
=666*1000-666*333+222*999
=666000-6*3*111*111+2*9*111*111
=666000
666✘667+222✘999
=666*666+666+222*999
=111*111*6*6+111*111*2*9+666
=111*111*(36+18)+666
=111*111*54+111*6
=111*(111*54+6)
=111*6000
=666000
6666ⅹ667十2222
=(1+666)×667+222×3×333
=1×667+666×667+666×333
=667+666×(667+333)
=667+666×1000
=667+666000
=666667