Group {1,−1, i,−i} Cordial Labeling of sum of Cn and Km for some m

Let G be a (p,q) graph and A be a group. We denote the order of an element a ∈ A by o(a). Let f : V (G) → A be a function. For each edge uv assign the label 1 if (o(f(u)), o(f(v))) = 1or 0 otherwise. f is called a group A Cordial labeling if |vf (a) − vf (b)| ≤ 1 and |ef (0) − ef (1)| ≤ 1, where vf (x) and ef (n) respectively denote the number of vertices labelled with an element x and number of edges labelled with n(n = 0, 1). A graph which admits a group A Cordial labeling is called a group A Cordial graph. In this paper we define group {1,−1, i,−i} Cordial graphs and characterize the graphs Cn + Km(2 ≤ m ≤ 5) that are group {1,−1, i,−i} Cordial.