GenerateGraph.ToStringWithNeighbors C# (CSharp) Method

    public string ToStringWithNeighbors()
    {
        string return_string = "";
        Dictionary<Node, int> pairToNodes =
            new Dictionary<Node, int>();
        for (int i = 0; i < nodes.Count; i++) {
            pairToNodes.Add (nodes[i], i);
        }
        for (int i = 0; i < nodes.Count; i++) {
            return_string += "\n" + "Node: " + i + " has neighbors ";
            for (int j = 0; j < nodes[i].neighbors.Count; j++) {
                return_string += pairToNodes[nodes[i].neighbors[j]] + ", ";
            }
        }
        return return_string;
    }