A spanning subgraph is a subgraph uas muaj tag nrho cov vertices ntawm thawj daim duab. Ib tsob ntoo spanning yog ib qho spanning subgraph uas feem ntau nyiam. Lub voj voog nyob rau hauv daim duab uas muaj tag nrho cov vertices ntawm daim duab yuav raug hu ua lub voj voog ncig.
Puas muaj pes tsawg daim subgraphs muaj?
Muaj 2n induced subgraphs (tag nrho subsets of vertices) thiab 2m spanning subgraphs (tag nrho subsets of edges).
Yuav ua li cas thiaj nrhiav tau ib daim ntawv txuas ntxiv?
Thiab los ntawm kev txhais ntawm Spanning subgraph ntawm daim duab G yog subgraph tau los ntawm ntug kev tshem tawm nkaus xwb. Yog tias peb ua subsets ntawm ntug los ntawm kev rho tawm ib ntug, ob ntug, peb ntug thiab lwm yam. Raws li muaj m npoo ces muaj 2^m subsets. Li no G muaj 2^m spanning subgraphs.
txhais tau tias ntawm tsob ntoo?
Tus ntoo ncua ntawm daim duab (G) yog ib ntu ntawm G uas npog tag nrho nws cov vertices siv qhov tsawg kawg nkaus ntawm cov npoo. Qee cov khoom ntawm tsob ntoo spanning tuaj yeem txiav tawm los ntawm cov ntsiab lus no: Txij li "ib tsob ntoo spanning npog tag nrho cov vertices", nws tsis tuaj yeem txiav tawm.
Dab tsi yog spanning graph theory?
Ib tsob ntoo spanning yog subset ntawm Graph G, uas muaj tag nrho cov vertices them nrog yam tsawg kawg nkaus tus naj npawb ntawm ntug. Yog li ntawd, ib tsob ntoo spanning tsis muaj voj voog thiab nws tsis tuaj yeem txiav tsis tau.. Los ntawm lub ntsiab lus no, peb tuaj yeem txiav txim siab tias txhua qhov txuas thiab tsis ncaj qha Graph G muaj tsawg kawg yog ib tsob ntoo ncua.
