Solving L(2,1)-labeling Problem of Graphs using Genetic Algorithms

L(2,1)-labeling of a graph G is a function f: V(G) → {0, 1, 2, ...} such that |f(u) – f(v)| ≥ 2 when d(u, v) = 1 and |f(u) – f(v)| ≥ 1 when d(u, v) = 2. L(2,1)-labeling number of G, denoted by λ(G), is the smallest number m such that G has an L(2,1)-labeling with no label greater than m. Since this problem has been proved to be NP-complete, in this article, we develop genetic algorithms for L(2,1)-labeling problem and show that the suggested genetic algorithm peforms very efficiently by applying the algorithms to the class of graphs with known optimum values.