Added earliest deadline first scheduling algo

scheduling/shortest_deadline_first.py

@@ -0,0 +1,64 @@
+'''
+Earliest Deadline First (EDF) Scheduling Algorithm
+
+This code implements the Earliest Deadline First (EDF)
+scheduling algorithm, which schedules processes based on their deadlines.
+If a process cannot meet its deadline, it is marked as "Idle."
+
+Reference: 
+https://www.geeksforgeeks.org/earliest-deadline-first-edf-cpu-scheduling-algorithm/
+
+Author: Arunkumar
+Date: 14th October 2023
+'''
+
+def earliest_deadline_first_scheduling(processes: list[tuple[str, int, int, int]]) -> list[str]:
+    """
+    Perform Earliest Deadline First (EDF) scheduling.
+
+    Args:
+        processes (List[Tuple[str, int, int, int]]): A list of processes with their names,
+            arrival times, deadlines, and execution times.
+
+    Returns:
+        List[str]: A list of process names in the order they are executed.
+
+    Examples:
+        >>> processes = [("A", 1, 5, 2), ("B", 2, 8, 3), ("C", 3, 4, 1)]
+        >>> execution_order = earliest_deadline_first_scheduling(processes)
+        >>> execution_order
+        ['Idle', 'A', 'C', 'B']
+
+    """
+    result = []
+    current_time = 0
+
+    while processes:
+        available_processes = [
+            process for process in processes if process[1] <= current_time
+        ]
+
+        if not available_processes:
+            result.append("Idle")
+            current_time += 1
+        else:
+            next_process = min(
+                available_processes, key=lambda x: x[2]
+            )
+            name, _ , deadline, execution_time = next_process
+
+            if current_time + execution_time <= deadline:
+                result.append(name)
+                current_time += execution_time
+                processes.remove(next_process)
+            else:
+                result.append("Idle")
+                current_time += 1
+
+    return result
+
+if __name__ == "__main__":
+    processes = [("A", 1, 5, 2), ("B", 2, 8, 3), ("C", 3, 4, 1)]
+    execution_order = earliest_deadline_first_scheduling(processes)
+    for i, process in enumerate(execution_order):
+        print(f"Time {i}: Executing process {process}")