42 lines
989 B
Python
42 lines
989 B
Python
"""
|
|
Input: Start and finish time of n jobs
|
|
Output: Schedule with maximum number of non overlapping jobs
|
|
The Strategy: At each step choose the job with earliest finish time
|
|
Algorithm Type: Greedy
|
|
Time Complexity: O(n*log(n))
|
|
"""
|
|
jobs = [
|
|
(0, 2, 8), # (job_id, start_time, finish_time)
|
|
(1, 6, 10),
|
|
(2, 1, 3),
|
|
(3, 4, 7),
|
|
(4, 3, 6),
|
|
(5, 1, 2),
|
|
(6, 8, 10),
|
|
(7, 10, 15),
|
|
(8, 12, 16),
|
|
(9, 14, 16)
|
|
]
|
|
|
|
|
|
def get_opt_schedule(jobs):
|
|
"""
|
|
Return the job_id's in the optimal jobs
|
|
https://en.wikipedia.org/wiki/Interval_scheduling#Greedy_polynomial_solution
|
|
|
|
>>> get_opt_schedule(jobs)
|
|
[5, 4, 1, 7]
|
|
"""
|
|
opt_schedule = []
|
|
sorted_jobs = sorted(jobs, key=lambda j: j[2])
|
|
number_of_jobs = len(sorted_jobs)
|
|
opt_schedule.append(sorted_jobs[0][0])
|
|
for i in range(1, number_of_jobs):
|
|
if sorted_jobs[i][1] >= jobs[opt_schedule[-1]][2]:
|
|
opt_schedule.append(sorted_jobs[i][0])
|
|
return opt_schedule
|
|
|
|
|
|
if __name__ == "__main__":
|
|
print(get_opt_schedule(jobs))
|