c++ Linked List Memory Bug - c++

Question

For an assignment i have to build this. I just can't seem to see what i am doing wrong. When I am trying to run this code I keep seeing the pointer that my linked list stores it's starting location get pointed to garbage right in the middle. I don't know if Visual Studio is just hazing me or if I am miss assigning a pointer somewhere.
This is the main class i use to run my code
#include "stdafx.h"
#include "Iterator.h"
#include "Node.h"
#include "List.h"
#include <iostream>
int main()
{
int input = 0;
List<double> salaryList;
std::cin >> input;
Node<double> tim(7.0, nullptr);
Node<double> sim(input, nullptr);
Node<double> jim(7.5, nullptr);
salaryList.Add_back(&jim);
salaryList.Add_back(&tim);
salaryList.Insert_front(&sim);
Iterator<double> checkSalaries=salaryList.begin();
//std::cout << "printing all elements in Iterator" << std::endl;
while (checkSalaries.Is_item()){
double x = (*checkSalaries).value;
std::cout << x << std::endl;
checkSalaries++;
}
system("PAUSE");
return 0;
}
This is the code for the LinkedList, i just named it List :
#include "Iterator.h"
#include "Node.h"
template <class t>
class List
{
private:
Node<t>* start=nullptr;
Node<t>* end=nullptr;
int size = 0;
public:
List() {
start = nullptr;
end = nullptr;
}
~List() {
}
void Insert_front(Node<t> * input) {
if (start != nullptr)
{
input->setPoint(start);
start = input;
size++;
}
else {
start = input;
}
if (start->point != nullptr && end == nullptr) {
end = start->point;
size++;
}
}
void Add_back(Node<t> * input) {
if (end != nullptr) {
Node<t> temp = (*end);
temp.setPoint(input);
end = input;
}
else {
if (start != nullptr) {
start->point=input;
end = input;
}
else {
start = input;
}
size++;
}
}
Iterator<t> begin() const
{
Node<t> tempNode = *start;
Iterator<t> temp(&tempNode);
return temp;
}
void Remove_all()
{
List<Node<t>> temp;
start = temp.start;
end = temp.end;
size = 0;
}
int Size() const {
return size;
}
};
This is the Node code:
template <class T>
class Node {
public:
T value;
Node<T> * point;
Node(T first, Node<T> * second)
{
value = first;
point = second;
}
Node()
{
value = NULL;
point = nullptr;
}
void setPoint(Node<T> * input) {
point = input;
}
};
I am going to include here two images the first is what it looks like just before it goes bad, and the next is what happens right after, it seems to occur fairly at random but i have found that using cout always triggers it so i commented out that line, though that didn't resolve the issue.
Good StateBad State

Answer 1

On my first review, it seems the local variable in begin method is creating the issue. Please check my code below. I have commented out the temporary variable created in the begin method and instead made use of the pointer start. This should solve the issue.
Iterator<t> begin() const
{
// Node<t> tempNode = *start; <-- A local variable is used here
// Iterator<t> temp(&tempNode); <-- address of local variable passed to iterator.
Iterator<t> temp(start);
return temp;
}