1 files changed, 174 insertions, 0 deletions
diff --git a/2020/Rust/src/day5.rs b/2020/Rust/src/day5.rs
new file mode 100644
index 0000000..ad48295
--- /dev/null
+++ b/2020/Rust/src/day5.rs
@@ -0,0 +1,174 @@
+use std::{
+    fs::{self, File},
+    io::{self, BufRead, BufReader, Write},
+    sync::{Arc, Mutex},
+    thread,
+};
+
+#[derive(Debug, Clone)]
+enum TaskStatus {
+    Pending,
+    Completed,
+}
+
+#[derive(Debug, Clone)]
+struct Task {
+    id: usize,
+    description: String,
+    status: TaskStatus,
+}
+
+impl Task {
+    fn new(id: usize, description: String) -> Self {
+        Self {
+            id,
+            description,
+            status: TaskStatus::Pending,
+        }
+    }
+
+    fn mark_done(&mut self) {
+        self.status = TaskStatus::Completed;
+    }
+
+    fn to_string(&self) -> String {
+        format!(
+            "{}|{}|{}",
+            self.id,
+            self.description,
+            match self.status {
+                TaskStatus::Pending => "Pending",
+                TaskStatus::Completed => "Completed",
+            }
+        )
+    }
+
+    fn from_string(data: &str) -> Option<Self> {
+        let parts: Vec<&str> = data.split('|').collect();
+        if parts.len() != 3 {
+            return None;
+        }
+        let id = parts[0].parse().ok()?;
+        let description = parts[1].to_string();
+        let status = match parts[2] {
+            "Pending" => TaskStatus::Pending,
+            "Completed" => TaskStatus::Completed,
+            _ => return None,
+        };
+
+        Some(Self {
+            id,
+            description,
+            status,
+        })
+    }
+}
+
+#[derive(Debug)]
+struct TaskManager {
+    tasks: Vec<Task>,
+}
+
+impl TaskManager {
+    fn new() -> Self {
+        Self { tasks: vec![] }
+    }
+
+    fn add_task(&mut self, description: String) {
+        let id = self.tasks.len() + 1;
+        let task = Task::new(id, description);
+        self.tasks.push(task);
+    }
+
+    fn mark_task_done(&mut self, id: usize) -> Result<(), String> {
+        match self.tasks.iter_mut().find(|t| t.id == id) {
+            Some(task) => {
+                task.mark_done();
+                Ok(())
+            }
+            None => Err(format!("Task with ID {} not found.", id)),
+        }
+    }
+
+    fn list_tasks(&self) {
+        for task in &self.tasks {
+            println!(
+                "ID: {}, Description: {}, Status: {:?}",
+                task.id, task.description, task.status
+            );
+        }
+    }
+
+    fn save_to_file(&self, filename: &str) -> io::Result<()> {
+        let mut file = File::create(filename)?;
+        for task in &self.tasks {
+            writeln!(file, "{}", task.to_string())?;
+        }
+        Ok(())
+    }
+
+    fn load_from_file(&mut self, filename: &str) -> io::Result<()> {
+        self.tasks.clear();
+        let file = File::open(filename)?;
+        let reader = BufReader::new(file);
+        for line in reader.lines() {
+            if let Ok(line) = line {
+                if let Some(task) = Task::from_string(&line) {
+                    self.tasks.push(task);
+                }
+            }
+        }
+        Ok(())
+    }
+}
+
+fn add(x: i32, y: i32, z: i32) -> i32 {
+    x + y + z
+}
+
+fn main() {
+    let task_manager = Arc::new(Mutex::new(TaskManager::new()));
+
+    let xay = 5;
+    let yay = 6;
+    let x = xay + yay + add(xay, yay, 3);
+    let y = 2;
+
+    // let z = add(x, y);
+
+    let tm_clone = Arc::clone(&task_manager);
+    println!(
+        "tm_clone: {:?}, Arc::clone(&task_manager): {:?}",
+        tm_clone,
+        Arc::clone(&task_manager)
+    );
+    thread::spawn(move || {
+        let mut tm = tm_clone.lock().unwrap();
+        tm.add_task("Learn Rust".to_string());
+        tm.add_task("Build a project".to_string());
+        tm.list_tasks();
+    })
+    .join()
+    .unwrap();
+
+    let tm_clone = Arc::clone(&task_manager);
+    thread::spawn(move || {
+        let mut tm = tm_clone.lock().unwrap();
+        tm.mark_task_done(1)
+            .unwrap_or_else(|err| println!("{}", err));
+        tm.list_tasks();
+    })
+    .join()
+    .unwrap();
+
+    let tm_clone = Arc::clone(&task_manager);
+    thread::spawn(move || {
+        let mut tm = tm_clone.lock().unwrap();
+        let filename = "tasks.txt";
+        tm.save_to_file(filename).expect("Failed to save tasks");
+        tm.load_from_file(filename).expect("Failed to load tasks");
+        tm.list_tasks();
+    })
+    .join()
+    .unwrap();
+}