added algorithm for FCFS scheduling

Author: deepakumarvu

FCFS/fcfs.py

@@ -1,18 +1,19 @@
-import random
 process_queue = []
 total_wtime = 0
-n = 10
-print 'Input : '
-print 'ProcessName\tArrivalTime\tBurstTime'
+n = int(raw_input('Enter number of process: '))
 for i in xrange(n):
     process_queue.append([])#append a list object to the list
     process_queue[i].append(i+1)
-    process_queue[i].append(random.randint(0,51))
-    process_queue[i].append(random.randint(1,11))
+    process_queue[i].append(int(raw_input('Enter p_arrival: ')))
+    while process_queue[i][1]>50 or process_queue[i][1]<0:
+    	process_queue[i][1]=int(raw_input('Enter p_arrival(Should be between 0-50 sec): '))
+    total_wtime += process_queue[i][1]
+    process_queue[i].append(int(raw_input('Enter p_bust: ')))
+    while process_queue[i][2]>10 or process_queue[i][2]<0:
+    	process_queue[i][2]=int(raw_input('Enter p_burst(Should be between 0-10 msec): '))
     process_queue[i].append(process_queue[i][1])
-    print process_queue[i][0],'\t\t',process_queue[i][1],'\t\t',process_queue[i][2]
-	
-
+    print ''
+    
 process_queue.sort(key = lambda process_queue:process_queue[1])
 exe=process_queue[0][1]+process_queue[0][2];
 for j in xrange(n-1):
@@ -23,7 +24,10 @@
 		process_queue[i][3]=exe
 		exe=exe+process_queue[i][2]
 
-print 'Output : '
+ 
 print 'ProcessName\tArrivalTime\tBurstTime\tExecutionStartTime'
 for i in xrange(n):
     print process_queue[i][0],'\t\t',process_queue[i][1],'\t\t',process_queue[i][2],'\t\t',process_queue[i][3]
+     
+print 'Total waiting time: ',total_wtime
+print 'Average waiting time: ',(total_wtime/n)