From efb0b723b155a3cc900657358eb1c65a3431a0a8 Mon Sep 17 00:00:00 2001
From: SquidSpirit <squid@squidspirit.com>
Date: Fri, 19 Sep 2025 00:21:19 +0800
Subject: [PATCH] feat: 3408_design_task_manager

---
 3408_design_task_manager/Cargo.lock |  7 +++
 3408_design_task_manager/Cargo.toml |  6 +++
 3408_design_task_manager/src/lib.rs | 78 +++++++++++++++++++++++++++++
 3 files changed, 91 insertions(+)
 create mode 100644 3408_design_task_manager/Cargo.lock
 create mode 100644 3408_design_task_manager/Cargo.toml
 create mode 100644 3408_design_task_manager/src/lib.rs

diff --git a/3408_design_task_manager/Cargo.lock b/3408_design_task_manager/Cargo.lock
new file mode 100644
index 0000000..2b5184a
--- /dev/null
+++ b/3408_design_task_manager/Cargo.lock
@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "design_task_manager"
+version = "0.1.0"
diff --git a/3408_design_task_manager/Cargo.toml b/3408_design_task_manager/Cargo.toml
new file mode 100644
index 0000000..99d45a5
--- /dev/null
+++ b/3408_design_task_manager/Cargo.toml
@@ -0,0 +1,6 @@
+[package]
+name = "design_task_manager"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]
diff --git a/3408_design_task_manager/src/lib.rs b/3408_design_task_manager/src/lib.rs
new file mode 100644
index 0000000..3831f89
--- /dev/null
+++ b/3408_design_task_manager/src/lib.rs
@@ -0,0 +1,78 @@
+use std::collections::{BinaryHeap, HashMap};
+
+#[derive(Clone, PartialEq, Eq)]
+pub struct Task {
+    pub uid: i32,
+    pub pid: i32,
+    pub priority: i32,
+}
+
+impl Ord for Task {
+    fn cmp(&self, other: &Self) -> std::cmp::Ordering {
+        self.priority
+            .cmp(&other.priority)
+            .then(self.pid.cmp(&other.pid))
+            .then(self.uid.cmp(&other.uid))
+    }
+}
+
+impl PartialOrd for Task {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        Some(self.cmp(other))
+    }
+}
+
+pub struct TaskManager {
+    tasks: HashMap<i32, Task>,
+    max_heap: BinaryHeap<Task>,
+}
+
+impl TaskManager {
+    pub fn new(tasks_vec: Vec<Vec<i32>>) -> Self {
+        let tasks_iter = tasks_vec.iter().map(|t| Task {
+            uid: t[0],
+            pid: t[1],
+            priority: t[2],
+        });
+
+        Self {
+            tasks: HashMap::from_iter(tasks_iter.clone().map(|t| (t.pid, t))),
+            max_heap: BinaryHeap::from_iter(tasks_iter),
+        }
+    }
+
+    pub fn add(&mut self, uid: i32, pid: i32, priority: i32) {
+        let task = Task { uid, pid, priority };
+        self.tasks.insert(pid, task.clone());
+        self.max_heap.push(task);
+    }
+
+    pub fn edit(&mut self, pid: i32, new_priority: i32) {
+        let task = self.tasks.get_mut(&pid).unwrap();
+        task.priority = new_priority;
+        self.max_heap.push(task.clone());
+    }
+
+    pub fn rmv(&mut self, pid: i32) {
+        self.tasks.remove(&pid);
+    }
+
+    pub fn exec_top(&mut self) -> i32 {
+        let mut result_task: Option<Task> = None;
+
+        while let Some(top_task) = self.max_heap.peek() {
+            if let Some(task) = self.tasks.get(&top_task.pid)
+                && task == top_task
+            {
+                result_task = Some(task.clone());
+                self.tasks.remove(&top_task.pid);
+                self.max_heap.pop();
+                break;
+            } else {
+                self.max_heap.pop();
+            }
+        }
+
+        result_task.map_or(-1, |t| t.uid)
+    }
+}