根据班名分系部

=IF(ISNUMBER(FIND(LEFT(B2,2),"网络物联信息广告设计动画")),"计算机系",IF(ISNUMBER(FIND(LEFT(B2,2),"机电汽修数控")),"机电系",IF(ISNUMBER(FIND(LEFT(B2,2),"电商")),"电商系","经管系")))