Q. 61 Consider an undirected graph G where self-loops are not allowed. The vertex set of G is {(i, j): 1 <= i <= 12, 1 <= j <= 12}. There is an edge between (a, b) and (c, d) if |a − c| <= 1 and |b − d| <= 1.
The number of edges in this graph is __________.
(A) 500
(B) 502
(C) 506
(D) 510
Answer: (C)
Explanation:
