CS8_Notes.txt

//4 things you must always have in a class: Default constructor, Copy constructor, equal operator, destructor.

// ++it (increments the item, 1 step)
// it++ (check the value of the item, then increment the value of the item, 2 steps)

//std:pair<char,int> ('z',200) //z is the index, 200 is the value

The difference between a class and a struc is that in a structure everything is public by default and a class is private by default. For class u need to use "public:" to have the same effect

1const something& (2const pointer &blah) 3const 
1:returned value cannot be changed
2:promises original input will not be changed
3: nothing can be changed inside the function


DOUBLE LINK LIST
insertBeforeHead() or insertMiddle()
insertAfterTail()
deleteNode()
data = T();// T() fires the default constructor for that data type (T is a template)


when inserting in the middle make 2 references before deleting one. Repeat for the other direction.
how ever u write it out, u have to be able to read it back in again. (ostream operator<<(ostream &out, const T &output))

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STACKS

template<typename T>
(T*)theData() // theData() is a void pointer, which u cannot dereference. Typecast (T*) gives us the type it's returning whether it be an int, double, string, etc...
once you typecast (T*) a void pointer theData(), you can dereference it like so, *(T*) theData(); "(T*)" is typecasting. In "T*" the "*" means a pointer to T. *(T*) is dereferencing that typecast (ie: *(int*))

a void pointer is a pointer that can point to anything, whether it be a char an int or a class. All pointers have the same size, but what it is pointing to does not.
So to find out the bit size of the the data the void pointer is pointing to we have to dereference it. We dereference void pointers when you need to write or read from it.




if(in>>data)//try to read the data, if the data cannot be found, skip it.
	other.getData() = data;
	
	return in;
	
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-------------------------POINTERS TO FUNCTIONS---------------------
The functions we know and love are actually function pointers that point to a function stored in memory

functions pointers can only point to functions with the same signatures. IE [int *fptr (int, int)] can only point to [int function(int, int)]






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BINARY TREE
2*N+1(left side), 2*N+2(right side)
2^(N-1)-1(# of nodes at my depth)

BINARY SEARCH TREE (BST)
1.) Is a binary tree
2.) has an called ordering lessthan
3.) if a child is lessthan its parent, it is on the left branch of the parent
4.) if it is not lessthan, it is on the right edge

1.) Balanced 
		AVL Tree
			an AVL tree is a binary tree such that the difference in depth(depth is distance from me to the furthest node, counting myself) of the left 
				
			A binary tree such that the difference in depth if the left sub-tree and the right subtree is less than or equal to 1.

	In Order
		There are 3 "output" transverses
			inorder
				go leftDown as far as you can, then do a horizontal zigzag while print out the data inside.(see notes)
			preorder
				root is first (see notes)
			postorder
				root is last(see notes)
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demorgans law
if (!something && !somethingElse) is the same as if (!(something || somethingElse)) latter is far more efficient.




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HASH (A unique function such that a key will always give you the same index) ctime has a function to time the speed of your program.

-use luhn algorithm
-

-first number/letter represents what kind of card it is (visa credit)
-next 4 numbers tells us what bank
-next 4 tells us what branch
-last number before the ^ is the ceck sum/hash result, tells us if card is valid or not


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BIN SORT

-mergesort is one of the best sorting algorithms

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FINAL
marble api (displays maps)