mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-10-06 13:49:30 +00:00
bc8df6de31
* [pre-commit.ci] pre-commit autoupdate updates: - [github.com/astral-sh/ruff-pre-commit: v0.2.2 → v0.3.2](https://github.com/astral-sh/ruff-pre-commit/compare/v0.2.2...v0.3.2) - [github.com/pre-commit/mirrors-mypy: v1.8.0 → v1.9.0](https://github.com/pre-commit/mirrors-mypy/compare/v1.8.0...v1.9.0) * [pre-commit.ci] auto fixes from pre-commit.com hooks for more information, see https://pre-commit.ci --------- Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
64 lines
1.9 KiB
Python
64 lines
1.9 KiB
Python
"""
|
|
Given a list of tasks, each with a deadline and reward, calculate which tasks can be
|
|
completed to yield the maximum reward. Each task takes one unit of time to complete,
|
|
and we can only work on one task at a time. Once a task has passed its deadline, it
|
|
can no longer be scheduled.
|
|
|
|
Example :
|
|
tasks_info = [(4, 20), (1, 10), (1, 40), (1, 30)]
|
|
max_tasks will return (2, [2, 0]) -
|
|
Scheduling these tasks would result in a reward of 40 + 20
|
|
|
|
This problem can be solved using the concept of "GREEDY ALGORITHM".
|
|
Time Complexity - O(n log n)
|
|
https://medium.com/@nihardudhat2000/job-sequencing-with-deadline-17ddbb5890b5
|
|
"""
|
|
|
|
from dataclasses import dataclass
|
|
from operator import attrgetter
|
|
|
|
|
|
@dataclass
|
|
class Task:
|
|
task_id: int
|
|
deadline: int
|
|
reward: int
|
|
|
|
|
|
def max_tasks(tasks_info: list[tuple[int, int]]) -> list[int]:
|
|
"""
|
|
Create a list of Task objects that are sorted so the highest rewards come first.
|
|
Return a list of those task ids that can be completed before i becomes too high.
|
|
>>> max_tasks([(4, 20), (1, 10), (1, 40), (1, 30)])
|
|
[2, 0]
|
|
>>> max_tasks([(1, 10), (2, 20), (3, 30), (2, 40)])
|
|
[3, 2]
|
|
>>> max_tasks([(9, 10)])
|
|
[0]
|
|
>>> max_tasks([(-9, 10)])
|
|
[]
|
|
>>> max_tasks([])
|
|
[]
|
|
>>> max_tasks([(0, 10), (0, 20), (0, 30), (0, 40)])
|
|
[]
|
|
>>> max_tasks([(-1, 10), (-2, 20), (-3, 30), (-4, 40)])
|
|
[]
|
|
"""
|
|
tasks = sorted(
|
|
(
|
|
Task(task_id, deadline, reward)
|
|
for task_id, (deadline, reward) in enumerate(tasks_info)
|
|
),
|
|
key=attrgetter("reward"),
|
|
reverse=True,
|
|
)
|
|
return [task.task_id for i, task in enumerate(tasks, start=1) if task.deadline >= i]
|
|
|
|
|
|
if __name__ == "__main__":
|
|
import doctest
|
|
|
|
doctest.testmod()
|
|
print(f"{max_tasks([(4, 20), (1, 10), (1, 40), (1, 30)]) = }")
|
|
print(f"{max_tasks([(1, 10), (2, 20), (3, 30), (2, 40)]) = }")
|