Shortest Job First Scheduling Algorithm Implementation

sjf.py

#!/usr/bin/python2
print 'Enter number of processes'
n, proc_in, time, proc_queue = int(raw_input()), [], 0, []

for i in xrange(n):
    proc = []
    print 'Enter PID'
    proc.append(raw_input())
    print 'Enter arrival time'
    proc.append(int(raw_input()))
    print 'Enter execution time'
    proc.append(int(raw_input()))
    proc_in.append(proc)

proc_in.sort(key = lambda proc_in:proc_in[1])
proc_queue = []

foo = []
i = 0
while i < n:
    at = proc_in[i][1]
    while i < n and proc_in[i][1] == at:
        foo.append(proc_in[i])
        i = i+1
    foo.sort(key = lambda foo:foo[2])
    for proc in foo:
        proc_queue.append(proc)
    foo = []
    

for proc in proc_queue:
    time = time if time > proc[1] else proc[1]
    time = time + proc[2]
    proc.append(time)
    proc.append(proc[3] - proc[2] - proc[1] if time > proc[1] else 0)
    
print '\n'
print '{:<4} {:<12} {:<12} {:<12} {:<12}'.format(*'PID_Arrival Time_Burst Time_Waiting Time_Finish Time'.split('_'))
for proc in proc_queue:
    print '{:<4} {:<12} {:<12} {:<12} {:<12}'.format(proc[0],proc[1],proc[2],proc[4],proc[3])