PD mean cordial labeling of graphs

Let G = (V, E) be a simple graph. Let f be a map from V(G) to {1,2}. We associate two integers P = f(u)f(v) and $D=⌊f(u)f(v)⌋$⁠, where f(u) ≥ f(v). For each edge uv assign the label $⌊P+D2⌋$⁠. Then f is called PD mean cordial labeling if |v_f(i) – v_f(j)| ≤ 1 and |e_f(i) – e_f(j)| ≤ 1, i, j ∈ {1, 2}, where v_f(x) and e_f(x) denote the number of vertices and edges labelled with x (x = 1,2) respectively. A graph G is PD mean cordial if it satisfies PD mean cordial labeling. In this paper we study the PD mean cordial labeling of some tree graphs.