The fault tolerance problem of semi-paired,many to many and k-disjoint path cover(k-DPC)on unit interval graphs is studied.Using the structural characteristics of the path cover and the structural properties of the vertex order of the unit interval graphs,the unit interval graphs with semi-paired 1-DPC and k-DPC properties are characterized.At the same time,we obtain the relevant results of the unit interval graph G:for any vertex set W and any edge set F,G-W passing through F has the semi-paired 1-DPC property if and only if G is(2+r)-connected,where| W|=p,|F|=q,p+q≤r;G-W passing through F has the semi-paired k-DPC property if and only if G is(2k+r-l)-connected,where k≥2.It is shown that the existence of disjoint path covers in graphs is closely related to vertex connectivity and Hamiltonian properties.The research methods and results provide a theoretical basis for further study of the path coverage of interval graphs and other related graphs.
unit interval graphsemi-paired k-DPCfault tolerancepath cover