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Problem with a reverse function in a template class stack implementation

djanthony93 (2)
this is my stack implementation using template with a struct type node and a class type stack:
Stack.h
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	#ifndef STACK_H_
	#define STACK_H_
	
	#include <cstdlib>
	#include <iostream>
	#include <cassert>
	
	using namespace std;
	
	template <class t>
	struct node{
		t data;
		node<t>* next;
	};
	
	template <class t>
	class stack
	{
	public:
		stack();
		~stack();
		bool isEmpty(){ return (top_ptr=NULL);};
		void push(const t&);
		void pop();
		t top() const;
		void reverse();
		void clear();
		void print();
	private:
		node<t>* top_ptr;
	};
	
	template <class t>
	stack<t>::stack()
	{
		top_ptr=NULL;
	}
	
	template <class t>
	stack<t>::~stack()
	{
		while(top_ptr != NULL) pop();
	}
	
	template <class t>
	void stack<t>::push(const t& source)
	{
		node<t>* new_node = new node<t>;
		new_node->data = source;
		new_node->next = top_ptr;
		top_ptr = new_node;
		cout << "Inserito!" << endl;
	}
	
	template <class t>
	void stack<t>::pop()
	{
		node<t>* remove = top_ptr;
		top_ptr = top_ptr->next;
		delete remove;
		cout << "Rimosso!" << endl;
	}
	
	template <class t>
	t stack<t>::top() const
	{
		assert(top_ptr != NULL);
		return top_ptr->data;
	}
	
	template <class t>
	void stack<t>::clear()
	{
		node<t>* temp;
		while(top_ptr != NULL)
		{
			temp = top_ptr;
			top_ptr = top_ptr->next;
			delete temp;
		}
		cout << "Clear completato!" << endl;
	}
	
	template <class t>
	void stack<t>::reverse()
	{
		stack<t> new_stack;
		while(top_ptr != NULL)
		{
			new_stack.push(top_ptr->data);
			pop();
		}
		cout << "Reverse completato!" << endl;
	}
	
	template <class t>
	void stack<t>::print()
	{
		node<t>* ptr = top_ptr;
		while(ptr!=NULL)
		{
			cout << " " << ptr->data << endl;
			ptr = ptr->next;
		}
	}
	
	#endif /* STACK_H_ */

And this is the main.cpp:

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    #include "stack.h"
	
	int main()
	{
		stack<int> stackino;
		for(int i = 0; i<10; i++) stackino.push(i);
		stackino.pop();
		cout << "top(): " << stackino.top() << endl;
		stackino.print();
		cout << "Invoco clear()" << endl;
		stackino.clear();
		cout << "Stackino dopo clear():" << endl;
		stackino.print();
		cout << "Invoco reverse()" << endl;
		stackino.reverse();
		cout << "Stackino dopo reverse()" << endl;
		stackino.print();
	
		cout << "FINE!" << endl;
		return 0;
	}

The problem is reverse() that causes a crash of the program, I guess "top_ptr = new_stack.top_ptr" is wrong but it makes compile and execute, but crashes. Someone can help me correct this?
Thank you very much!
Lachlan Easton (699)
When does it crash? It doesn't crash for me https://ideone.com/iA02LO

output:
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Inserito!
Rimosso!
top(): 8
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 7
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 5
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 3
 2
 1
 0
Invoco clear()
Clear completato!
Stackino dopo clear():
Invoco reverse()
Reverse completato!
Stackino dopo reverse()
FINE!
djanthony93 (2)
Sorry I forgot an instruction in the reverese() function, try this:

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template <class t>
	void stack<t>::reverse()
	{
		stack<t> new_stack;
		while(top_ptr != NULL)
		{
			new_stack.push(top_ptr->data);
			pop();
		}
		cout << "Reverse completato!" << endl;
                top_ptr = new_stack.top_ptr;
	}

I want to make the old top_ptr as the new_stack.top_ptr, but when I try to print the stack, it print nothing
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