public void UpdatingAndGettingEdgeWeight()
{
var vertices = new int[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
var graph = new WeightedALGraph <int, int>();
graph.AddVertices(vertices);
Assert.IsTrue(graph.VerticesCount == vertices.Length);
foreach (var vertex in vertices)
{
Assert.IsTrue(graph.ContainsVertex(vertex));
}
// Graph is:
// 1 <-> 2, 3, 4
// 2 <-> 1, 3, 5, 6
// 3 <-> 1, 2, 6
// 4 <-> 1, 6, 7
// 5 <-> 2, 7, 8
// 6 <-> 2, 3, 4
// 7 <-> 4, 8
// 8 <-> 7, 5
// 9 <->
// With each edge having a weight of the sum of its vertices
graph.AddEdge(1, 2, 3);
graph.AddEdge(1, 3, 4);
graph.AddEdge(1, 4, 5);
graph.AddEdge(2, 3, 5);
graph.AddEdge(2, 5, 7);
graph.AddEdge(2, 6, 8);
graph.AddEdge(3, 6, 9);
graph.AddEdge(4, 6, 10);
graph.AddEdge(4, 7, 11);
graph.AddEdge(5, 7, 12);
graph.AddEdge(5, 8, 13);
graph.AddEdge(7, 8, 15);
int weight = 0;
Assert.IsTrue(graph.TryGetEdgeWeight(1, 2, out weight));
Assert.IsTrue(weight == 3);
Assert.IsTrue(graph.UpdateEdgeWeight(1, 2, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(2, 1, out weight));
Assert.IsTrue(weight == 6);
Assert.IsTrue(graph.TryGetEdgeWeight(1, 3, out weight));
Assert.IsTrue(weight == 4);
Assert.IsTrue(graph.UpdateEdgeWeight(1, 3, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(3, 1, out weight));
Assert.IsTrue(weight == 8);
Assert.IsTrue(graph.TryGetEdgeWeight(1, 4, out weight));
Assert.IsTrue(weight == 5);
Assert.IsTrue(graph.UpdateEdgeWeight(1, 4, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(4, 1, out weight));
Assert.IsTrue(weight == 10);
Assert.IsTrue(graph.TryGetEdgeWeight(2, 3, out weight));
Assert.IsTrue(weight == 5);
Assert.IsTrue(graph.UpdateEdgeWeight(2, 3, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(3, 2, out weight));
Assert.IsTrue(weight == 10);
Assert.IsTrue(graph.TryGetEdgeWeight(2, 5, out weight));
Assert.IsTrue(weight == 7);
Assert.IsTrue(graph.UpdateEdgeWeight(2, 5, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(5, 2, out weight));
Assert.IsTrue(weight == 14);
Assert.IsTrue(graph.TryGetEdgeWeight(2, 6, out weight));
Assert.IsTrue(weight == 8);
Assert.IsTrue(graph.UpdateEdgeWeight(2, 6, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(6, 2, out weight));
Assert.IsTrue(weight == 16);
Assert.IsTrue(graph.TryGetEdgeWeight(3, 6, out weight));
Assert.IsTrue(weight == 9);
Assert.IsTrue(graph.UpdateEdgeWeight(3, 6, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(6, 3, out weight));
Assert.IsTrue(weight == 18);
Assert.IsTrue(graph.TryGetEdgeWeight(4, 6, out weight));
Assert.IsTrue(weight == 10);
Assert.IsTrue(graph.UpdateEdgeWeight(4, 6, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(6, 4, out weight));
Assert.IsTrue(weight == 20);
Assert.IsTrue(graph.TryGetEdgeWeight(4, 7, out weight));
Assert.IsTrue(weight == 11);
Assert.IsTrue(graph.UpdateEdgeWeight(4, 7, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(7, 4, out weight));
Assert.IsTrue(weight == 22);
Assert.IsTrue(graph.TryGetEdgeWeight(5, 7, out weight));
Assert.IsTrue(weight == 12);
Assert.IsTrue(graph.UpdateEdgeWeight(5, 7, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(7, 5, out weight));
Assert.IsTrue(weight == 24);
Assert.IsTrue(graph.TryGetEdgeWeight(5, 8, out weight));
Assert.IsTrue(weight == 13);
Assert.IsTrue(graph.UpdateEdgeWeight(5, 8, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(8, 5, out weight));
Assert.IsTrue(weight == 26);
Assert.IsTrue(graph.TryGetEdgeWeight(7, 8, out weight));
Assert.IsTrue(weight == 15);
Assert.IsTrue(graph.UpdateEdgeWeight(7, 8, weight * 2));
Assert.IsTrue(graph.TryGetEdgeWeight(8, 7, out weight));
Assert.IsTrue(weight == 30);
}