/** * Template method, which can be configured by overriding the three * primitive operations below. */ private Assignment recursiveBackTrackingSearch(CSP csp, Assignment assignment) { Assignment result = null; if (assignment.isComplete(csp.getVariables())) { result = assignment; } else { Variable var = selectUnassignedVariable(assignment, csp); foreach (Object value in orderDomainValues(var, assignment, csp)) { assignment.setAssignment(var, value); fireStateChanged(assignment, csp); if (assignment.isConsistent(csp.getConstraints(var))) { DomainRestoreInfo info = inference(var, assignment, csp); if (!info.isEmpty()) fireStateChanged(csp); if (!info.isEmptyDomainFound()) { result = recursiveBackTrackingSearch(csp, assignment); if (result != null) break; } info.restoreDomains(csp); } assignment.removeAssignment(var); } } return result; }
private bool revise(Variable var, Constraint constraint, Assignment assignment, CSP csp, DomainRestoreInfo info) { bool revised = false; foreach (Object value in csp.getDomain(var)) { assignment.setAssignment(var, value); if (!constraint.isSatisfiedWith(assignment)) { info.storeDomainFor(var, csp.getDomain(var)); csp.removeValueFromDomain(var, value); revised = true; } assignment.removeAssignment(var); } return(revised); }
/** * Template method, which can be configured by overriding the three * primitive operations below. */ private Assignment recursiveBackTrackingSearch(CSP csp, Assignment assignment) { Assignment result = null; if (assignment.isComplete(csp.getVariables())) { result = assignment; } else { Variable var = selectUnassignedVariable(assignment, csp); foreach (Object value in orderDomainValues(var, assignment, csp)) { assignment.setAssignment(var, value); fireStateChanged(assignment, csp); if (assignment.isConsistent(csp.getConstraints(var))) { DomainRestoreInfo info = inference(var, assignment, csp); if (!info.isEmpty()) { fireStateChanged(csp); } if (!info.isEmptyDomainFound()) { result = recursiveBackTrackingSearch(csp, assignment); if (result != null) { break; } } info.restoreDomains(csp); } assignment.removeAssignment(var); } } return(result); }
private bool revise(Variable var, Constraint constraint, Assignment assignment, CSP csp, DomainRestoreInfo info) { bool revised = false; foreach (Object value in csp.getDomain(var)) { assignment.setAssignment(var, value); if (!constraint.isSatisfiedWith(assignment)) { info.storeDomainFor(var, csp.getDomain(var)); csp.removeValueFromDomain(var, value); revised = true; } assignment.removeAssignment(var); } return revised; }