我有以下定义：
class PartitioningMethod {
public:
virtual void addConstraints(ConstraintManager& cm) = 0;
virtual bool hasMoreConstraints() = 0;
virtual void setQuery(const Query& q) = 0;
virtual ~PartitioningMethod(){ }
};
class Random : public PartitioningMethod {
private:
vector< ref<Expr> > constraints;
vector< ref<Expr> >::iterator it;
vector< ref<Expr> >::iterator end;
int numConstraints;
RNG theRNG;
public:
void setQuery(const Query& q) {
constraints.clear();
//Set random number
//srand ( unsigned ( time (NULL) ) * theRNG.getInt32() );
srand ( theRNG.getInt32() );
//Copy constraints
copy(q.constraints.begin(),q.constraints.end(),std::back_inserter(constraints));
//Shuffle Randomly
std::random_shuffle(constraints.begin(),constraints.end(), p_myrandom);
it = constraints.begin();
end = constraints.end();
numConstraints = constraints.size();
}
void addConstraints(ConstraintManager& cm) {
int step = rand() % numConstraints + 1;
while(step != 0) {
cm.addConstraint(*it);
++it;
--step;
--numConstraints;
}
}
bool hasMoreConstraints() {
return it != end;
}
};
bool PartitioningSolver::computeInitialValues(const Query& query,
const std::vector<const Array*> &objects,
std::vector< std::vector<unsigned char> > &values,
bool &hasSolution) {
fprintf(stderr,"INIT\n");
// If there are no constraints in the query
if(query.constraints.size() == 0 || query.constraints.size() == 1)
return solver->impl->computeInitialValues(query, objects, values, hasSolution);
// If the number constraints in the query are > 0
method->setQuery(query);
ConstraintManager cm;
ref<Expr> expr = query.expr;
fprintf(stderr,"Begin partitioning\n");
fprintf(stderr,"---------------------\n");
while(method->hasMoreConstraints()){
fprintf(stderr, "HERE");
//Add Constraints
method->addConstraints(cm);
//Construct a query
Query temp_query(cm,expr);
ExprPPrinter::printQuery(std::cerr,temp_query.constraints,temp_query.expr);
fprintf(stderr,"---------------------\n");
//Query STP to check if satisfiable
values.clear();
if(!solver->impl->computeInitialValues(temp_query, objects, values, hasSolution))
return false;
//If not, return immediately (a win!)
if(!hasSolution)
return true;
//If a solution is returned, check if the solution satisfies the entire set of constraints
vector<const Array*> obj = objects;
Assignment solution(obj, values);
bool satisfiesAll = checkSolution(solution, query.constraints);
// fprintf(stderr,"Satisfies all: %i\n", satisfiesAll);
// If it is successful, return the solution (a win again!),
if(satisfiesAll)
return true;
// If not add more constraints (if there is more) and repeat
}
return true;
}
Partitioning求解器类的部分定义：
class PartitioningSolver : public SolverImpl {
private:
Solver* solver;
PartitioningMethod* method;
bool checkSolution(Assignment& solution, const ConstraintManager& constraints);
public:
PartitioningSolver(Solver *s, PartitioningMethod* pm) : solver(s), method(pm) { }
~PartitioningSolver() { delete solver; delete method; }
};
很抱歉粘贴了这么长的代码片段，但我已经研究了几个小时并且不断收到错误
pure virtual method called
terminate called without an active exception
我不确定出了什么问题。它所在的 computeInitialValues 函数似乎失败了fprintf(stderr,"Begin partitioning\n");。我尝试添加打印语句作为最后的手段，但即使它们不打印任何东西..任何想法都值得赞赏。
编辑：
好的，所以我将名称 Random 更改为 Ran 并开始工作。我正在动态创建这个类实例作为 new Random() 的参数我猜它与另一个构造函数或其他我不知道的东西混合在一起。