/**
* Recursive backtracking search method using the remaining problem. This method contains the algorithm
* for the backtracking search.
*/
private ScheduleState recursiveBacktrackingSearch(CSPSearchAgent remainingProblem)
{
//Check if the problem is complete.
if (remainingProblem.isComplete())
{
//If so, return the completed scheduleState
return remainingProblem.getScheduleState();
}
//Retrieve an array of successorStates from the CSPSearchAgent.
List<ScheduleState> successorStates = remainingProblem.getSuccessors();
//Loop through the successor states.
foreach (ScheduleState state in successorStates)
{
//Create a new CSPSearchAgent using the new successor state
CSPSearchAgent nextProblem = new CSPSearchAgent(state);
//If the problem does not violate constraints
if (nextProblem.checkConstraints() == true)
{
//Recursively search the next set.
ScheduleState result = recursiveBacktrackingSearch(nextProblem);
//If the result from the recursion is null,
if (result == null)
{
//continue with the next state in the for loop.
continue;
}
//Otherwise,
else
{
//return the result.
return result;
}
}
}
//If no solution is found, return null.
return null;
}
/**
* Recursive backtracking search method using the remaining problem. This method contains the algorithm
* for the backtracking search.
*/
private ScheduleState recursiveBacktrackingSearch(CSPSearchAgent remainingProblem)
{
//Check if the problem is complete.
if (remainingProblem.isComplete())
{
//If so, return the completed scheduleState
return(remainingProblem.getScheduleState());
}
//Retrieve an array of successorStates from the CSPSearchAgent.
List <ScheduleState> successorStates = remainingProblem.getSuccessors();
//Loop through the successor states.
foreach (ScheduleState state in successorStates)
{
//Create a new CSPSearchAgent using the new successor state
CSPSearchAgent nextProblem = new CSPSearchAgent(state);
//If the problem does not violate constraints
if (nextProblem.checkConstraints() == true)
{
//Recursively search the next set.
ScheduleState result = recursiveBacktrackingSearch(nextProblem);
//If the result from the recursion is null,
if (result == null)
{
//continue with the next state in the for loop.
continue;
}
//Otherwise,
else
{
//return the result.
return(result);
}
}
}
//If no solution is found, return null.
return(null);
}
/**
* Backtracking search method that returns the completed schedule state. This is the search called
* by the form. The recursive method defines the business operations.
*/
public ScheduleState backtrackingSearch(CSPSearchAgent startingProblem)
{
//Calls to the recursive method for backtracking search.
return recursiveBacktrackingSearch(startingProblem);
}
/**
* Backtracking search method that returns the completed schedule state. This is the search called
* by the form. The recursive method defines the business operations.
*/
public ScheduleState backtrackingSearch(CSPSearchAgent startingProblem)
{
//Calls to the recursive method for backtracking search.
return(recursiveBacktrackingSearch(startingProblem));
}
