U2R2+(R+R2) R 10 所以R+R2U100×103-1)×1×10=999 DR R2=99-R1=90K U3R2+(R+R2+R3) U R R+R+R.=Cn-1-=.100-110=999 100×10 R3=999-R1-R2=900k2 爆件大师    = − − = −  = − + + = − = + + + = = − = −   =   + = − = + + = − R R R k k U U R R R R R R R R U U R R k R U U R R R R R R U U g g g g g g g g g g k 999 900 10 999 100 10 100 99 90 1 10 99 100 10 10 ( 3 1 2 3 3 1 2 3 3 1 2 3 2 1 3 3 2 1 2 2 2 1) 3 ( 1) ( ( ) ( 1) ( 1) ) 所以