Time bound solvers

Interfaces/SolverInterface.cs

@@ -1,6 +1,3 @@
-using API.Interfaces.JSON_Objects;
-using API.Interfaces.JSON_Objects.Graphs;
-using API.Tools;
 
 namespace API.Interfaces;
 
@@ -10,6 +7,21 @@ interface ISolver {
     string source {get;}
     string[] contributors { get; }
 
+    bool timerHasExpired { get; set; }
+
+    /// <summary>
+    /// Called when the run time timer for this solver has run out. The solver is
+    /// expected to check the "timerHasExpired" periodically and abandon the solution
+    /// if the flag is found to be true.
+    /// </summary>
+    public void TimerExpired()
+    {
+        timerHasExpired = true;
+    }
+    public void ResetTimer()
+    {
+        timerHasExpired = false;
+    }
     string solve(string problem);
 
     List<string> GetSteps(string instance)
@@ -23,10 +35,29 @@ string ISolver.solve(string problem) {
         // Should there be some sort of contraint that assures there is a constructor
         // that matches the signature of a single `string` argument?
         // Perhaps a static `FromInstance(string instance)` method for `IProblem` will work.
-        return solve((T)Activator.CreateInstance(typeof(T), problem));
+        T problemInstance = (T)Activator.CreateInstance(typeof(T), problem);
+        if (problemInstance == null)
+            throw new ArgumentException($"Could not create problem instance for {problem}.");
+
+        string result = "no solution found";
+        Thread thread = new Thread(() => result = solve(problemInstance));
+
+        // start the thread
+        ResetTimer();
+        thread.Start();
+
+        // after 5 seconds w/out finishing, tell the thread it's time
+        // is up and wait for it to finish up.
+        // XXX make the solution time configurable
+        if (thread.Join(new TimeSpan(0, 0, 5)) == false)
+        {
+            TimerExpired();
+            thread.Join();
+        }
+        return result;
     }
-    string solve(T problem);
 
+    string solve(T problem);
 
     List<string> ISolver.GetSteps(string instance)
     {

Problems/NPComplete/NPC_ARCSET/Solvers/ArcSetBruteForce.cs

@@ -13,6 +13,7 @@ class ArcSetBruteForce : ISolver<ARCSET> {
     public string source {get;} = "";
 
     public string[] contributors {get;} = { "Alex Diviney","Caleb Eardley","Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public ArcSetBruteForce() {

Problems/NPComplete/NPC_BERNSTEINVAZIRANI/Solvers/BernsteinVaziraniClassicalSolver.cs

@@ -8,6 +8,7 @@ class BernsteinVaziraniClassicalSolver : ISolver<BERNSTEINVAZIRANI> {
     public string solverDefinition { get; } = "This is a classical verifier for the Bernstein-Vazirani problem which runs in O(n) time.";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Jason L. Wright" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public BernsteinVaziraniClassicalSolver() {}

Problems/NPComplete/NPC_CLIQUE/Solvers/CliqueBruteForce.cs

@@ -12,6 +12,7 @@ class CliqueBruteForce : ISolver<CLIQUE> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Clique problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Caleb Eardley", "Kaden Marchetti"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public CliqueBruteForce() {

Problems/NPComplete/NPC_CLIQUECOVER/Solvers/CliqueCoverBruteForce.cs

@@ -10,6 +10,7 @@ class CliqueCoverBruteForce : ISolver<CLIQUECOVER> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Clique Cover problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public CliqueCoverBruteForce()

Problems/NPComplete/NPC_CUT/Solvers/CutBruteForce.cs

@@ -10,8 +10,9 @@ class CutBruteForce : ISolver<CUT> {
     public string solverDefinition {get;} = "This is a brute force solver for the Cut problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Andrija Sevaljevic"};
+    public bool timerHasExpired { get; set; }
 
-public CutBruteForce() {
+    public CutBruteForce() {
 
     }
     private long factorial(long x){

Problems/NPComplete/NPC_DEUTSCH/Solvers/DeutschClassicalSolver.cs

@@ -8,6 +8,7 @@ class DeutschClassicalSolver : ISolver<DEUTSCH> {
     public string solverDefinition {get;} = "This is a classical solver for the Deutsch Problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Jason L. Wright" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public DeutschClassicalSolver() {}

Problems/NPComplete/NPC_DEUTSCHJOZSA/Solvers/DeutschJozsaClassicalSolver.cs

@@ -10,6 +10,7 @@ class DeutschJozsaClassicalSolver : ISolver<DEUTSCHJOZSA> {
     public string solverDefinition {get;} = "This is a classical solver for the Deutsch Jozsa Problem";
     public string source {get;} = "TODO";
     public string[] contributors {get;} = { "George Lake", "Eric Hill", "Paul Gilbreath", "Max Gruenwoldt", "Alex Svancara" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public DeutschJozsaClassicalSolver() {}

Problems/NPComplete/NPC_DIRECTEDHAMILTONIAN/Solvers/DirectedHamiltonianBruteForce.cs

@@ -10,6 +10,7 @@ class DirectedHamiltonianBruteForce : ISolver<DIRECTEDHAMILTONIAN> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Directed Hamiltonian Path problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public DirectedHamiltonianBruteForce()

Problems/NPComplete/NPC_DM3/Solvers/ThreeDimensionalMatchingBruteForce.cs

@@ -9,6 +9,7 @@ class ThreeDimensionalMatchingBruteForce : ISolver<DM3> {
     public string solverDefinition {get;} = "This is a generic local search solver for 3-Dimensional Matching, which, while possible, removes one constraint from the current solution, and swaps in two more constraints.";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Caleb Eardley"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public ThreeDimensionalMatchingBruteForce() {

Problems/NPComplete/NPC_EXACTCOVER/Solvers/DancingLinks.cs

@@ -9,6 +9,7 @@ class DancingLinks : ISolver<EXACTCOVER> {
     public string solverDefinition {get;} = "";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public DancingLinks() {

Problems/NPComplete/NPC_EXACTCOVER/Solvers/ExactCoverBruteForce.cs

@@ -8,6 +8,7 @@ class ExactCoverBruteForce : ISolver<EXACTCOVER> {
     public string solverDefinition {get;} = "This is a generic brute force solver for Exact Cover";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Caleb Eardley"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public ExactCoverBruteForce() {

Problems/NPComplete/NPC_EXACTCOVER/Solvers/ExactCoverRecursive.cs

@@ -8,6 +8,7 @@ class ExactCoverRecursive : ISolver<EXACTCOVER> {
     public string solverDefinition {get;} = "This is a optimized recursive solver for Exact Cover";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public ExactCoverRecursive() {

Problems/NPComplete/NPC_GRAPHCOLORING/Solvers/GraphColoringBruteForce.cs

@@ -10,6 +10,7 @@ class GraphColoringBruteForce : ISolver<GRAPHCOLORING> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Graph Coloring problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public GraphColoringBruteForce()

Problems/NPComplete/NPC_HAMILTONIAN/Solvers/HamiltonianBruteForce.cs

@@ -10,6 +10,7 @@ class HamiltonianBruteForce : ISolver<HAMILTONIAN> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Hamiltonian Path problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public HamiltonianBruteForce()

Problems/NPComplete/NPC_HITTINGSET/Solvers/HittingSetBruteForce.cs

@@ -11,6 +11,7 @@ class HittingSetBruteForce : ISolver<HITTINGSET> {
     public string solverDefinition {get;} = "This is a brute force solver for Hitting Set";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public HittingSetBruteForce() {

Problems/NPComplete/NPC_INDEPENDENTSET/Solvers/IndependentSetBruteForce.cs

@@ -10,6 +10,7 @@ class IndependentSetBruteForce : ISolver<INDEPENDENTSET> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Independent Set problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public IndependentSetBruteForce() {

Problems/NPComplete/NPC_INTPROGRAMMING01/Solvers/IntegerProgrammingBruteForce.cs

@@ -8,6 +8,7 @@ class IntegerProgrammingBruteForce : ISolver<INTPROGRAMMING01> {
     public string solverDefinition {get;} = "This is a generic brute force solver for 0-1 Integer Programming";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Caleb Eardley"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public IntegerProgrammingBruteForce() {

Problems/NPComplete/NPC_JOBSEQ/Solvers/JobSeqBruteForce.cs

@@ -10,6 +10,7 @@ class JobSeqBruteForce : ISolver<JOBSEQ> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Job Sequencing problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public JobSeqBruteForce() {

Problems/NPComplete/NPC_KNAPSACK/Solvers/KnapsackBruteForce.cs

@@ -10,6 +10,7 @@ class KnapsackBruteForce : ISolver<KNAPSACK> {
     public string solverDefinition {get;} = "This a brute force solver for the 0-1 Knapsack problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Russell Phillips"};
+    public bool timerHasExpired { get; set; }
 
 
     public string complexity {get;} = "O(2^n)";

Problems/NPComplete/NPC_NODESET/Solvers/NodeSetBruteForce.cs

@@ -10,8 +10,9 @@ class NodeSetBruteForce : ISolver<NODESET> {
     public string solverDefinition {get;} = "This is a brute force solver for the Node Set problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Andrija Sevaljevic"};
+    public bool timerHasExpired { get; set; }
 
-public NodeSetBruteForce() {
+    public NodeSetBruteForce() {
 
     }
     private long factorial(long x){

Problems/NPComplete/NPC_PARTITION/Solvers/PartitionBruteForce.cs

@@ -10,6 +10,7 @@ class PartitionBruteForce : ISolver<PARTITION> {
     public string solverDefinition {get;} = "This is a brute force solver for the Partition problem";
     public string source {get;} = "";
     public string[] contributors {get;} = {"Andrija Sevaljevic"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public PartitionBruteForce() {

Problems/NPComplete/NPC_SAT/Solvers/SATBruteForceSolver.cs

@@ -17,6 +17,7 @@ public class SATBruteForceSolver : ISolver {
     public string solverDefinition {get;} = "This is a simple brute force solver for SAT";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Daniel Igbokwe, Show Pratoomratana"};
+    public bool timerHasExpired { get; set; }
 
     #endregion
 
@@ -117,7 +118,10 @@ public string solve(string SATInstance){
         // Loop through all combinations. The total number of binary choices you can make is 2^(number of items). E.G. 3 variables is 2^3.
         for (int currentCombination = 0; currentCombination < Math.Pow(2, literals.Count); currentCombination++){
             int trueClauses = 0;
-                foreach (List<string> currentClause in clause){
+            if (timerHasExpired)
+                return "timeout";
+
+            foreach (List<string> currentClause in clause){
                     // change the T/F values of the literals. Starts with at least 1 being true by incrementing at the start.
                     literalDict = increment(literalDict); 
                     bool currentEvaluation = evaluate(literalDict, currentClause);

Problems/NPComplete/NPC_SAT3/Solvers/Sat3BacktrackingSolver.cs

@@ -11,6 +11,7 @@ class Sat3BacktrackingSolver : ISolver<SAT3> {
     public string solverDefinition {get;} = "This is a O(n!) solution algorithm for the 3SAT problem which implements a back tracking algorithm to find and exact assignment boolean assignment of variable to satisfy the broblem instance.";
     public string source {get;} = "";
     public string[] contributors {get;} = {"David Lindeman","Kaden Marchetti"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public Sat3BacktrackingSolver() {

Problems/NPComplete/NPC_SETCOVER/Solvers/HeuristicSolver.cs

@@ -9,6 +9,7 @@ class HeuristicSolver : ISolver<SETCOVER> {
     public string solverDefinition {get;} = "";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public HeuristicSolver()

Problems/NPComplete/NPC_SETCOVER/Solvers/SetCoverBruteForce.cs

@@ -11,6 +11,7 @@ class SetCoverBruteForce : ISolver<SETCOVER> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Set Cover problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public SetCoverBruteForce()

Problems/NPComplete/NPC_STEINERTREE/Solvers/SteinerTreeBruteForce.cs

@@ -10,6 +10,7 @@ class SteinerTreeBruteForce : ISolver<STEINERTREE> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Steiner Tree problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public SteinerTreeBruteForce()

Problems/NPComplete/NPC_SUBSETSUM/Solvers/SubsetSumBruteForce.cs

@@ -8,6 +8,7 @@ class SubsetSumBruteForce : ISolver<SUBSETSUM> {
     public string solverDefinition {get;} = "This is a brute force solver for Subset Sum";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Caleb Eardley","Garret Stouffer"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public SubsetSumBruteForce() {

Problems/NPComplete/NPC_TSP/Solvers/TSPBruteForce.cs

@@ -10,6 +10,7 @@ class TSPBruteForce : ISolver<TSP> {
     public string solverDefinition {get;} = "This is a brute force solver for the NP-Complete Traveling Sales Person problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public TSPBruteForce()

Problems/NPComplete/NPC_VERTEXCOVER/Solvers/VertexCoverBruteForce.cs

@@ -11,6 +11,7 @@ class VertexCoverBruteForce : ISolver<VERTEXCOVER> {
     public string solverDefinition {get;} = "This solver simply tests combinations of nodes of size k until a solution is found, or all combinations are tested.";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Caleb Eardley"};
+    public bool timerHasExpired { get; set; }
 
     // --- Methods Including Constructors ---
     public VertexCoverBruteForce() {

Problems/NPComplete/NPC_WEIGHTEDCUT/Solvers/WeightedCutBruteForce.cs

@@ -10,6 +10,7 @@ class WeightedCutBruteForce : ISolver<WEIGHTEDCUT> {
     public string solverDefinition {get;} = "This is a brute force solver for the Weighted Cut problem";
     public string source {get;} = "";
     public string[] contributors {get;} = { "Andrija Sevaljevic" };
+    public bool timerHasExpired { get; set; }
 
     public WeightedCutBruteForce()
     {
@@ -126,4 +127,3 @@ public string solve(WEIGHTEDCUT cut)
         return "{}";
     }
 }
-