Nt1=ONi1+12+OMi1+12;Nt2=ONi2+12+OMi2+12
Nt1=ONi1+12-OMi1+12;Nt2=ONi2+12-OMi2+12Khi OM ⋮i1:Nt1+1Khi OM⋮ i2:Nt2+1
Ns1=k1-1=Km-1Ns2=k2-1=Kn-1Ns3=k3-1=Kl-1