Question

So i wrote a driver for class that uses a menu to test out different hashing techniques. What i have is an abstract class “BaseHash” with all virtual functions and 5 different child classes that hash in different ways. When i do this:

while (numChoice!=0){
        switch(numChoice){
        case 1: myList= &MyHashContainer(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 2: myList= &hash2(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 3: myList= &chainingHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 4: myList= &quadraticHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 5: myList= &DoubleHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;

        }
    }

I get a stack overflow error the moment main is called. The debugger doesnt even let me get one step out before throwing the error.

If it matters myList looks like this

BaseHash *myList;

If i comment out the code starting with while, it does not throw this error. I dont even know where to begin with why this might happen.

Answer 1

I figured this out. I forgot that the stack has only a limited space on it, and i needed to use the “new” keyword to make sure all this was going on the heap

while (numChoice!=0){
        switch(numChoice){
        case 1: myList= new MyHashContainer(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 2: myList= new hash2(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 3: myList= new chainingHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 4: myList= new quadraticHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;
        case 5: myList= new DoubleHash(myStudentList.getStudentList(),myStudentList.getStudentList().size(),p);break;

        }
    }