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3408. Design Task Manager
Description
There is a task management system that allows users to manage their tasks, each associated with a priority. The system should efficiently handle adding, modifying, executing, and removing tasks.
Implement the TaskManager
class:
-
TaskManager(vector<vector<int>>& tasks)
initializes the task manager with a list of user-task-priority triples. Each element in the input list is of the form[userId, taskId, priority]
, which adds a task to the specified user with the given priority. -
void add(int userId, int taskId, int priority)
adds a task with the specifiedtaskId
andpriority
to the user withuserId
. It is guaranteed thattaskId
does not exist in the system. -
void edit(int taskId, int newPriority)
updates the priority of the existingtaskId
tonewPriority
. It is guaranteed thattaskId
exists in the system. -
void rmv(int taskId)
removes the task identified bytaskId
from the system. It is guaranteed thattaskId
exists in the system. -
int execTop()
executes the task with the highest priority across all users. If there are multiple tasks with the same highest priority, execute the one with the highesttaskId
. After executing, thetaskId
is removed from the system. Return theuserId
associated with the executed task. If no tasks are available, return -1.
Note that a user may be assigned multiple tasks.
Example 1:
Input:
["TaskManager", "add", "edit", "execTop", "rmv", "add", "execTop"]
[[[[1, 101, 10], [2, 102, 20], [3, 103, 15]]], [4, 104, 5], [102, 8], [], [101], [5, 105, 15], []]
Output:
[null, null, null, 3, null, null, 5]
Explanation
TaskManager taskManager = new TaskManager([[1, 101, 10], [2, 102, 20], [3, 103, 15]]); // Initializes with three tasks for Users 1, 2, and 3.taskManager.add(4, 104, 5); // Adds task 104 with priority 5 for User 4.
taskManager.edit(102, 8); // Updates priority of task 102 to 8.
taskManager.execTop(); // return 3. Executes task 103 for User 3.
taskManager.rmv(101); // Removes task 101 from the system.
taskManager.add(5, 105, 15); // Adds task 105 with priority 15 for User 5.
taskManager.execTop(); // return 5. Executes task 105 for User 5.
Constraints:
1 <= tasks.length <= 105
0 <= userId <= 105
0 <= taskId <= 105
0 <= priority <= 109
0 <= newPriority <= 109
- At most
2 * 105
calls will be made in total toadd
,edit
,rmv
, andexecTop
methods. - The input is generated such that
taskId
will be valid.
Solutions
Solution 1
-
class TaskManager { private final Map<Integer, int[]> d = new HashMap<>(); private final TreeSet<int[]> st = new TreeSet<>((a, b) -> { if (a[0] == b[0]) { return b[1] - a[1]; } return b[0] - a[0]; }); public TaskManager(List<List<Integer>> tasks) { for (var task : tasks) { add(task.get(0), task.get(1), task.get(2)); } } public void add(int userId, int taskId, int priority) { d.put(taskId, new int[] {userId, priority}); st.add(new int[] {priority, taskId}); } public void edit(int taskId, int newPriority) { var e = d.get(taskId); int userId = e[0], priority = e[1]; st.remove(new int[] {priority, taskId}); st.add(new int[] {newPriority, taskId}); d.put(taskId, new int[] {userId, newPriority}); } public void rmv(int taskId) { var e = d.remove(taskId); int priority = e[1]; st.remove(new int[] {priority, taskId}); } public int execTop() { if (st.isEmpty()) { return -1; } var e = st.pollFirst(); var t = d.remove(e[1]); return t[0]; } } /** * Your TaskManager object will be instantiated and called as such: * TaskManager obj = new TaskManager(tasks); * obj.add(userId,taskId,priority); * obj.edit(taskId,newPriority); * obj.rmv(taskId); * int param_4 = obj.execTop(); */
-
class TaskManager { private: unordered_map<int, pair<int, int>> d; set<pair<int, int>> st; public: TaskManager(vector<vector<int>>& tasks) { for (const auto& task : tasks) { add(task[0], task[1], task[2]); } } void add(int userId, int taskId, int priority) { d[taskId] = {userId, priority}; st.insert({-priority, -taskId}); } void edit(int taskId, int newPriority) { auto [userId, priority] = d[taskId]; st.erase({-priority, -taskId}); st.insert({-newPriority, -taskId}); d[taskId] = {userId, newPriority}; } void rmv(int taskId) { auto [userId, priority] = d[taskId]; st.erase({-priority, -taskId}); d.erase(taskId); } int execTop() { if (st.empty()) { return -1; } auto e = *st.begin(); st.erase(st.begin()); int taskId = -e.second; int userId = d[taskId].first; d.erase(taskId); return userId; } }; /** * Your TaskManager object will be instantiated and called as such: * TaskManager* obj = new TaskManager(tasks); * obj->add(userId,taskId,priority); * obj->edit(taskId,newPriority); * obj->rmv(taskId); * int param_4 = obj->execTop(); */
-
class TaskManager: def __init__(self, tasks: List[List[int]]): self.d = {} self.st = SortedList() for task in tasks: self.add(*task) def add(self, userId: int, taskId: int, priority: int) -> None: self.d[taskId] = (userId, priority) self.st.add((-priority, -taskId)) def edit(self, taskId: int, newPriority: int) -> None: userId, priority = self.d[taskId] self.st.discard((-priority, -taskId)) self.d[taskId] = (userId, newPriority) self.st.add((-newPriority, -taskId)) def rmv(self, taskId: int) -> None: _, priority = self.d[taskId] self.d.pop(taskId) self.st.remove((-priority, -taskId)) def execTop(self) -> int: if not self.st: return -1 taskId = -self.st.pop(0)[1] userId, _ = self.d[taskId] self.d.pop(taskId) return userId # Your TaskManager object will be instantiated and called as such: # obj = TaskManager(tasks) # obj.add(userId,taskId,priority) # obj.edit(taskId,newPriority) # obj.rmv(taskId) # param_4 = obj.execTop()