When I test my stack with an int when I do pop all it seems to return is the address of the thing that I want and not the value, which makes sense since I return something by reference.. but I just cant seem to figure out what to do to get around this.
What I need my .pop function to do is return a node, which is a pointer, and be able to copy that pointer to another pointer.
such as:
//TreeNode *child = myStack.pop();
that is what I need my code to do, but it is not working, can you all help?
template <typename T>
class Stack{
private:
std::vector<T> elems; // elements
public:
void push(T const&); // push element
T* pop(); // pop element
T top() const; // return top element
bool empty() const // return whether the stack is empty
{
return elems.empty();
}
};
template <typename T>
void Stack<T>::push(T const& elem){
elems.push_back(elem); // append copy of passed elem
}
template<typename T>
T* Stack<T>::pop(){
if (elems.empty()){
throw std::out_of_range("Stack<>::pop(): empty stack");
}
T value = elems.back();
elems.pop_back();
return &value;
}
template <typename T>
T Stack<T>::top() const{
if (elems.empty()){
throw std::out_of_range("Stack<>::top(): empty stack");
}
return elems.back(); // return copy of last element
}
this is what I have in my general tree class right now, to show you how I am implementing it
#include <iostream>
#include <fstream>
#include "Stack.h"
using namespace std;
class Tree{
private:
//inner node class
class TreeNode{
public:
//name of node
char name;
//number of children
int children;
//left most child
TreeNode *leftChild;
//right sibling
TreeNode *rightSibling;
//treenode constructor
TreeNode(char nodeName, int numChildren){
this->name = nodeName;
this->children = numChildren;
this->leftChild = NULL;
this->rightSibling = NULL;
}
};
//top of tree(stack form)
TreeNode *top;
public:
Tree::Tree(){
this->top = makeTree();
}
//tree creation
TreeNode* makeTree(){
//input file stream
ifstream fin;
//opens the file
fin.open("prog1.txt");
// Verifies file is opened correctly
if(!fin){
cout << "OOPS" << endl;
exit(1);
}
char name;
int count;
Stack<TreeNode> myStack;
do{
fin >> name >> count;
TreeNode *newNode = new TreeNode(name, count);
cout << newNode->name << newNode->children << endl;
cout << "here 1" << endl;
for(int kid = 0; kid < count; kid++){
//TreeNode *child = myStack.pop();
//cout << "here2" << endl;
//child->rightSibling = newNode->leftChild;
//newNode->leftChild = child;
//cout << child->name << child->children << endl;
}
myStack.push(*newNode);
cout << "also here" << endl;
TreeNode *myNode = myStack.pop();
cout << myNode->name << myNode->children << endl;
cout << "here3" << endl;
}while(!fin.eof());
return myStack.pop();
fin.close();
}
};
Unsolved 
