On a connected graph G, one may perform the following operations:[*]choose a vertice v, and add a vertice v′ such that v′ is connected to v and all of its neighbours
[*] choose a vertice v with odd degree and delete itShow that for any connected graph G, we may perform a finite number of operations such that the resulting graph is a clique.Proposed by idonthaveanaopsaccount graph theorycombinatorics