Help with Merging Lists

[jm92590]

Hey everyone, I've been assigned this problem for my course and I am COMPLETELY lost. I've spent the last 3 hours working on it, and even asked a friend or two with no results whatsoever. If anyone could help, that would be great.

* the comments are the instructions to complete the problem.

template <class Type>
void mergeLists(linkedListType<Type>& merged, linkedListType<Type>& list1,
                linkedListType<Type>& list2)
{
    linkedListIterator<int> itr;

    // TODO: Implement this function, which will merge list2 with list1 
    // and place the data into a new list call merge.

	
	merged = list;

	for (itr = list2.begin; itr != list2.end; itr++)
	{
		if (itr = NULL)
			return list1;
		else if (list1 = NULL)
			return itr;
		else if (itr < list1)
			
	}

	
	// Hints:
    // 1. Set merge equal to list
	// 2. Use a for loop to walk through the iterator on list2, for example:
    //    for (itr = list2.begin; /** etc.)
	// 3. Use an if-statement in the for-loop to check if the value of itr is
    //    in list1. Call the search() function. If it is insert itr in the 
    //    merge list.

    return;
}

As you can see I am completely lost when it comes to the third step, I have no idea of the proper syntax to use and I just feel overwhelmed. I think I am on the right track so far. (If I've messed up on the parts I've done please feel free to correct me)

Thank you in advance for the help, anything is great!