This code generates a shuffled Poker Deck. After that, drawNCards(deck, number_of_cards) function can be called to draw.
First, an ordered deck is built. Then a shuffle is made to get a random order deck which has exactly 1 copy of each card from the ordered deck. Then, a pointer is set to point the card on top and finally we can draw.
A Card is a struct which has two members: number and suit.
Number can go from 0 to 12 (2,3,4,5,6,7,8,9,10,J,Q,K,A are 13 cards)
Suit can go from 0 to 3 (Clubs, Spades, Diamonds, Hearts are 4 suits)
A Deck is a struct which contains a list of cards and a draw pointer called last_index, which contains the address of the following Card which is legal to draw.
When we draw, we get the card pointed by last_index. If more cards are being drawn, then the pointer decreases to not draw again the same card.
Shuffle is obtained by applying Fisher-Yates shuffle algorithm (with some auxiliar functions, since Cairo memory is immutable).
Pseudorandom number generation is achieved by implementing a Linear Congruential Generetor with mod 'm' = 22695477, increment 'c' = 1 and multiplier 'a' = 2^32
I have decided to use LCGs since they are implemented in many languages (like C) for rand() functions.
This project is my introduction to Cairo language. The goal was practicing some of the technical aspects such as references, variables, memory, sintax, structs, recursion, implicit args...
With some modifications this could be the base of a simple Poker Game.