//[TestMethod]
//public void InverseFloyWarshall10Test()
//{
// // Make a random 5-node undirected graph with designated connected components.
// // Computes transitive closure of using Floyd-Warshall
// InverseFWTest("IFW10", new[] { "1", "2", "3", "4", "5", "6", "7", "8", "9", "10" });
//}
//[TestMethod]
//public void InverseFloyWarshall20Test()
//{
// // Make a random 5-node undirected graph with designated connected components.
// // Computes transitive closure of using Floyd-Warshall
// InverseFWTest("IFW20", new[]
// {
// "1", "2", "3", "4", "5", "6", "7", "8", "9", "10",
// "11", "12", "13", "14", "15", "16", "17", "18", "19", "20"
// });
//}
private static void InverseFWTest(string name, string[] vertices)
{
var p = new Problem(name);
var adjacent = Predicate <string, string>("adjacent");
var floyd = Predicate <string, string, int>("d");
// Inlines either adjacent or floyd, depending on k
Proposition D(string v1, string v2, int k) => k == 0 ? adjacent(v1, v2) : floyd(v1, v2, k);
for (int k = 1; k < vertices.Length; k++)
{
var vk = vertices[k];
foreach (var v1 in vertices)
{
foreach (var v2 in vertices)
{
p.Assert(
D(v1, v2, k) <= D(v1, v2, k - 1),
D(v1, v2, k) <= (D(v1, vk, k - 1) & D(vk, v2, k - 1))
);
}
}
}
Proposition Connected(string v1, string v2) => D(v1, v2, vertices.Length - 1);
// Now constrain its connectivity
foreach (var v1 in vertices)
{
foreach (var v2 in vertices)
{
if (v1 == v2 || (v1 != "e" && v2 != "e"))
{
p.Assert(Connected(v1, v2));
}
else
{
p.Assert(Not(Connected(v1, v2)));
}
}
}
p.Optimize();
for (int i = 0; i < 100; i++)
{
var s = p.Solve();
// a, b, c, d should be a connected component, e should be unconnected to anything but e
foreach (var v1 in vertices)
{
foreach (var v2 in vertices)
{
Assert.IsTrue(s[Connected(v1, v2)] == (v1 == v2) || (v1 != "e" && v2 != "e"));
}
}
}
p.LogPerformanceData();
}