2. Cyclic judgment

If judgment For Loop

for i in range(1,5):        print i

for i in range(5):        print i

Use variables to control the number of cycles:

1. #!/usr/bin/pythonlist=[‘lk‘,‘tom‘,‘jack‘]a=4for name in range(1,a):        print name

Small exercise: Use for and if together

1. [[email protected] python_scripts]# cat 4for.py #!/usr/bin/pythonlist=[‘lk‘,‘tom‘,‘jack‘]for name in list:        if name==‘lk‘:                print name,‘ is very good!‘        else:                print nameprint ‘loop over!‘[[email protected] python_scripts]# python 4for.py lk  is very good!tomjackloop over!

While Loop

1. [[email protected] python_scripts]# cat 5while.py #!/usr/bin/pythonwhileTrue:        input=raw_input(‘(alive|dead|other):‘)        if input==‘alive‘:                print ‘The process is ‘,input        else:                print ‘The process is ‘,input                break

2. Cyclic judgment