Algorithms Question, thanks

Let G = (V, E) be an undirected graph with n nodes. A subset of the nodes is called an independent set if no two of them are joined by an edge. Finding large indepenedent sets is difficult in general; but here we will see that it can be done efficiently in a graph which is "simple" enough. It call thai a pr aph ( V X) a p th is; acolcs carl be writt n as h,"%- Mr, with an edge between vi and vj if and only if i and j differ by 1. Let each node vi have a positive integer weight wi, The goal of this question is to find an independent set in a path G whose total weight is as large as possible