basic implemenation of fcfs

- as if for now processess can't have same arrival time

Author: coderatul

cpu_sheduling.py

@@ -0,0 +1,112 @@
+import prettytable
+at_prcs_mapping = {} # arrivaltime : processess mapping
+bt_at_mapping = {} # burst time : arrival time mapping
+
+class CpuSheduling():
+    def __init__(self, name:list = [], arrival_time:list = [], burst_time:list = [], time_quantum= None) -> None:
+        self.process = name
+        self.arrival_time = arrival_time
+        self.burst_time = burst_time
+        self.time_quantum = time_quantum
+        
+        # displaying processess, arival time and burst time in a tabular format
+        print(10*"-","given process data",10*"-")
+        table = prettytable.PrettyTable()
+        table.field_names = ["Process", "Arrival Time", "Burst Time"]
+        for i in range(len(self.process)):
+            table.add_row([self.process[i], self.arrival_time[i], self.burst_time[i]])
+        print(table)
+        print()
+        
+    def fcfs(self):
+        """
+        first come first serve short term shdeuling
+        """
+        for i in range(len(self.process)):
+            # creating arrival time : process & burst time : arrival time mapping
+            at_prcs_mapping.update({self.arrival_time[i]:self.process[i]})
+            bt_at_mapping.update({self.arrival_time[i]:self.burst_time[i]})
+        
+        # sorted arriavl time 
+        self.arrival_time.sort()
+        
+        # burst time in order of process execution 
+        bt_ord = []
+
+        print("fcfs order: ",end="")
+        for k in self.arrival_time:
+            # printing keys(process) of arrival time(from sorted arrival time list(self.arrival_time))
+            if k == self.arrival_time[-1]:
+                print(f"{at_prcs_mapping.get(k)}",end="")
+            else:
+                print(f"{at_prcs_mapping.get(k)} -> ",end="")
+            
+            # appending burts time of process in the order of their execution
+            bt_ord.append(bt_at_mapping.get(k))
+        print()
+            
+        # calculating completion time of each process 
+        ct = []
+        for j in bt_ord:
+            if ct:
+                temp = ct[-1] + j
+            else:
+                temp = j
+            ct.append(temp)
+        
+        print()
+        print(30*"-","first come first serve shedule",30*"-")
+        print()
+        
+        # list of turn around time for everyprocess
+        tat_list = [a-b for a,b in zip(ct,at)]
+        
+        # average turn around time
+        tat = sum(tat_list) / len(tat_list)
+        
+        # list of waiting time for each process
+        wt_list = [a-b for a,b in zip(tat_list,bt)]
+        
+        # average waiting time
+        wt = sum(wt_list) / len(wt_list)
+        
+        # printing process, arival time, burst time, completion time, turn around time, waiting time
+        table = prettytable.PrettyTable()
+        table.field_names = ["Process", "Arrival Time", "Burst Time", "Completion Time", "Turn around time", "waiting time"]
+        for i in range(len(self.process)):
+            table.add_row([at_prcs_mapping.get(i), self.arrival_time[i], self.burst_time[i],ct[i],tat_list[i],wt_list[i]])
+        print(table)
+        print(f"turn around time -> {tat}")
+        print(f"average waiting time was -> {wt}")
+    
+    def sjf(self):
+        """
+        shortest job first: non-preemtive
+        """
+        ...
+        
+    def srtf(self):
+        """
+        shortest remaining time first : preemitive
+        """
+        ...
+        
+    def rr(self):
+        """
+        round robbin 
+        """
+        ...
+                       
+if __name__ == "__main__":
+    prcs = ["P1","P2","P3","P4","P5"] #process
+    at = [0,1,2,3,4] # arrival time
+    bt = [8,1,3,2,6] # burst time
+    shedule = CpuSheduling(prcs,at,bt) 
+    shedule.fcfs()
+    
+
+    
+    
+
+
+