Job sequencing with deadlines

greedy_methods/job_sequencing_with_deadline.py

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+"""
+This is a pure Python implementation of the greedy-merge-sort algorithm
+
+For doctests run following command:
+python3 -m doctest -v greedy_merge_sort.py
+"""
+
+
+# FUNCTION
+def job_sequencing_with_deadlines(num_jobs: int, jobs: list) -> list:
+    """
+    Function to find the maximum profit by doing jobs in a given time frame
+
+    Args:
+        num_jobs [int]: Number of jobs
+        jobs [list]: A list of tuples of (job_id, deadline, profit)
+
+    Returns:
+        max_profit [int]: Maximum profit that can be earned by doing jobs
+        in a given time frame
+
+    Examples:
+    >>> job_sequencing_with_deadlines(4, [(1, 4, 20), (2, 1, 10),
+    ... (3, 1, 40), (4, 1, 30)])
+    [2, 60]
+    >>> job_sequencing_with_deadlines(5, [(1, 2, 100), (2, 1, 19), 
+    ... (3, 2, 27), (4, 1, 25), (5, 1, 15)])
+    [2, 127]
+    """
+
+    # Sort the jobs in descending order of profit
+    jobs = sorted(jobs, key=lambda value: value[2], reverse=True)
+
+    # Create a list of size equal to the maximum deadline
+    # and initialize it with -1
+    max_deadline = max(jobs, key=lambda value: value[1])[1]
+    time_slots = [-1] * max_deadline
+
+    # Finding the maximum profit and the count of jobs
+    count = 0
+    max_profit = 0
+    for job in jobs:
+        # Find a free time slot for this job
+        # (Note that we start from the last possible slot)
+        for i in range(job[1] - 1, -1, -1):
+            if time_slots[i] == -1:
+                time_slots[i] = job[0]
+                count += 1
+                max_profit += job[2]
+                break
+    return [count, max_profit]
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()