1 files changed, 185 insertions, 0 deletions
diff --git a/2022/Rust/src/day5.rs b/2022/Rust/src/day5.rs
new file mode 100644
index 0000000..12ff7a8
--- /dev/null
+++ b/2022/Rust/src/day5.rs
@@ -0,0 +1,185 @@
+use std::{collections::VecDeque, num::ParseIntError, str::FromStr};
+
+const STACK_ELEMENT_WIDTH: usize = 3;
+const STACKS_SIZE: usize = 9;
+
+#[derive(Debug, Clone)]
+struct Stack {
+    stack: VecDeque<StackElement>,
+}
+
+impl FromStr for Stack {
+    type Err = ParseIntError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Ok(Stack {
+            stack: s
+                .lines()
+                .map(|line| line.parse::<StackElement>().unwrap())
+                .collect::<VecDeque<_>>(),
+        })
+    }
+}
+
+impl Stack {
+    fn new() -> Self {
+        Stack {
+            stack: VecDeque::new(),
+        }
+    }
+}
+
+#[derive(Debug, Clone)]
+struct StackElement {
+    ele: char,
+}
+
+impl FromStr for StackElement {
+    type Err = ParseIntError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let ch = s.chars().nth(1).unwrap();
+        Ok(StackElement { ele: ch })
+    }
+}
+
+#[derive(Debug)]
+struct Command {
+    num_of_times: usize,
+    from: usize,
+    target: usize,
+}
+
+impl FromStr for Command {
+    type Err = ParseIntError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        let s: Vec<usize> = s
+            .split_whitespace()
+            .collect::<Vec<_>>()
+            .iter()
+            .filter(|c| c.bytes().all(|c| c.is_ascii_digit()))
+            .map(|n| n.parse().unwrap())
+            .collect();
+        let (num_of_times, from, target) = (s[0], s[1], s[2]);
+        Ok(Command {
+            num_of_times,
+            from,
+            target,
+        })
+    }
+}
+
+fn apply_command(stacks: &mut Vec<Stack>, cmd: &Command, part1: bool) {
+    if part1 {
+        for _ in 0..cmd.num_of_times {
+            let element_to_push = stacks[cmd.from - 1].stack.pop_back().expect("welp the stack is empty");
+            stacks[cmd.target - 1].stack.push_back(element_to_push);
+        }
+    } else {
+        let mut tmp_stack :VecDeque<StackElement> = VecDeque::new();
+        for _ in 0..cmd.num_of_times {
+            let element_to_push = stacks[cmd.from - 1].stack.pop_back().expect("welp the stack is empty");
+            tmp_stack.push_back(element_to_push);
+        }
+        for _ in 0..cmd.num_of_times {
+            stacks[cmd.target - 1].stack.push_back(tmp_stack.pop_back().unwrap());
+        }
+    }
+}
+
+fn solve_part_one(data: &str) -> String {
+    let mut stacks: Vec<Stack> = vec![Stack::new(); STACKS_SIZE];
+    let stack = data.split("\n\n").nth(0).unwrap();
+    for x in stack.lines() {
+        let chars = x.chars().clone();
+        for (i, ch) in x.chars().enumerate() {
+            if ch == '[' {
+                stacks[i / 4].stack.push_front(
+                    chars.as_str()[i..i + STACK_ELEMENT_WIDTH]
+                        .parse::<StackElement>()
+                        .unwrap(),
+                )
+            }
+        }
+    }
+    let commands: Vec<Command> = data
+        .split("\n\n")
+        .nth(1)
+        .unwrap()
+        .lines()
+        .map(|command| command.parse::<Command>().unwrap())
+        .collect();
+
+    for cmd in &commands {
+        apply_command(&mut stacks, cmd, true);
+    }
+
+    let mut ans = "".to_string();
+    for i in 0..STACKS_SIZE {
+        if stacks[i].stack.len() >= 1 {
+            ans += stacks[i]
+                .stack
+                .iter()
+                .last()
+                .unwrap()
+                .ele
+                .to_string()
+                .as_str();
+        }
+    }
+    ans
+}
+
+fn solve_part_two(data: &str) -> String {
+    let mut stacks: Vec<Stack> = vec![Stack::new(); STACKS_SIZE];
+    let stack = data.split("\n\n").nth(0).unwrap();
+    for x in stack.lines() {
+        let chars = x.chars().clone();
+        for (i, ch) in x.chars().enumerate() {
+            if ch == '[' {
+                stacks[i / 4].stack.push_front(
+                    chars.as_str()[i..i + STACK_ELEMENT_WIDTH]
+                        .parse::<StackElement>()
+                        .unwrap(),
+                )
+            }
+        }
+    }
+    let commands: Vec<Command> = data
+        .split("\n\n")
+        .nth(1)
+        .unwrap()
+        .lines()
+        .map(|command| command.parse::<Command>().unwrap())
+        .collect();
+
+    for cmd in &commands {
+        apply_command(&mut stacks, cmd, false);
+    }
+
+    let mut ans = "".to_string();
+    for i in 0..STACKS_SIZE {
+        if stacks[i].stack.len() >= 1 {
+            ans += stacks[i]
+                .stack
+                .iter()
+                .last()
+                .unwrap()
+                .ele
+                .to_string()
+                .as_str();
+        }
+    }
+    ans
+}
+
+fn main() {
+    let data_test = include_str!("../data/day5.test");
+    let data_prod = include_str!("../data/day5.prod");
+
+    println!("part one test: {}", solve_part_one(data_test));
+    println!("part one prod: {}", solve_part_one(data_prod));
+    println!("part two test: {}", solve_part_two(data_test));
+    println!("part two prod: {}", solve_part_two(data_prod));
+}