Deck Shuffling

Implemented a deck shuffling algorithm. It will iterate over the deck of
cards 1000 times and swap the card it is on with another random card to
mix up the deck.

Cargo.lock

@@ -5,3 +5,144 @@ version = 4
 [[package]]
 name = "blackjack"
 version = "0.1.0"
+dependencies = [
+ "rand",
+]
+
+[[package]]
+name = "cfg-if"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9330f8b2ff13f34540b44e946ef35111825727b38d33286ef986142615121801"
+
+[[package]]
+name = "getrandom"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "899def5c37c4fd7b2664648c28120ecec138e4d395b459e5ca34f9cce2dd77fd"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "r-efi",
+ "wasip2",
+]
+
+[[package]]
+name = "libc"
+version = "0.2.180"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bcc35a38544a891a5f7c865aca548a982ccb3b8650a5b06d0fd33a10283c56fc"
+
+[[package]]
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+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85eae3c4ed2f50dcfe72643da4befc30deadb458a9b590d720cde2f2b1e97da9"
+dependencies = [
+ "zerocopy",
+]
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.105"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "535d180e0ecab6268a3e718bb9fd44db66bbbc256257165fc699dadf70d16fe7"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc74d9a594b72ae6656596548f56f667211f8a97b3d4c3d467150794690dc40a"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "r-efi"
+version = "5.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "69cdb34c158ceb288df11e18b4bd39de994f6657d83847bdffdbd7f346754b0f"
+
+[[package]]
+name = "rand"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6db2770f06117d490610c7488547d543617b21bfa07796d7a12f6f1bd53850d1"
+dependencies = [
+ "rand_chacha",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3022b5f1df60f26e1ffddd6c66e8aa15de382ae63b3a0c1bfc0e4d3e3f325cb"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.9.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "99d9a13982dcf210057a8a78572b2217b667c3beacbf3a0d8b454f6f82837d38"
+dependencies = [
+ "getrandom",
+]
+
+[[package]]
+name = "syn"
+version = "2.0.114"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d4d107df263a3013ef9b1879b0df87d706ff80f65a86ea879bd9c31f9b307c2a"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9312f7c4f6ff9069b165498234ce8be658059c6728633667c526e27dc2cf1df5"
+
+[[package]]
+name = "wasip2"
+version = "1.0.1+wasi-0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0562428422c63773dad2c345a1882263bbf4d65cf3f42e90921f787ef5ad58e7"
+dependencies = [
+ "wit-bindgen",
+]
+
+[[package]]
+name = "wit-bindgen"
+version = "0.46.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f17a85883d4e6d00e8a97c586de764dabcc06133f7f1d55dce5cdc070ad7fe59"
+
+[[package]]
+name = "zerocopy"
+version = "0.8.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "668f5168d10b9ee831de31933dc111a459c97ec93225beb307aed970d1372dfd"
+dependencies = [
+ "zerocopy-derive",
+]
+
+[[package]]
+name = "zerocopy-derive"
+version = "0.8.33"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c7962b26b0a8685668b671ee4b54d007a67d4eaf05fda79ac0ecf41e32270f1"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]

Cargo.toml

@@ -4,3 +4,4 @@ version = "0.1.0"
 edition = "2024"
 
 [dependencies]
+rand = "0.9.2"

src/deck.rs

@@ -1,4 +1,5 @@
 use super::card::Card;
+use rand::random_range;
 
 pub struct Deck {
     deck_size: u64,
@@ -9,7 +10,7 @@ pub struct Deck {
 impl Deck {
     pub fn new(num_decks: u64) -> Self {
         let deck_size: u64 = num_decks * 52;
-        let mut cards: Vec<Card> = Vec::new();
+        let mut cards: Vec<Card> = Vec::with_capacity(deck_size as usize);
 
         for card in 0..deck_size {
             let value = (card % 13) as u8;
@@ -38,4 +39,19 @@ impl Deck {
     pub fn deck_size(&self) -> usize {
         self.deck_size as usize
     }
+
+    pub fn cur_card(&self) -> u64 {
+        self.current_card
+    }
+
+    pub fn shuffle(&mut self) {
+        for _ in 0..1000 {
+            for card in 0..self.deck_size {
+                let swap_card = random_range(0..self.deck_size);
+                let save_card = self.cards[card as usize];
+                self.cards[card as usize] = self.cards[swap_card as usize];
+                self.cards[swap_card as usize] = save_card;
+            }
+        }
+    }
 }

tests/deck_tests.rs

@@ -5,6 +5,7 @@ fn check_num_decks() {
     let mut num_card: [u64; 52] = [0; 52];
     let num_decks = 8;
     let mut deck = Deck::new(num_decks as u64);
+    deck.shuffle();
 
     for _ in 0..deck.deck_size() {
         let next_card = deck.get_next_card();