Python if-elif-else

alien_color = ['green','yellow','red']
for color in alien_color:
   if color == 'green':
      print 'alien_color_%s: player to obtain five !'%color
   elif color == 'yellow':
      print 'alien_color_%s: player to obtain ten !' % color
   else:
      print 'alien_color_%s: player to obtain ten-five !' % color

try:
   age = input('please value a integer:') #####input输入的是整数，raw_input输入的是字符串
   if int(age) < 2:
      print 'he is a baby!'
   elif int(age) >= 2 and int(age) < 4:
      print 'he is going!'
   elif int(age)>= 4 and int(age) < 13:
      print 'he is a teenager!'
   elif int(age) >= 13 and int(age) < 65:
      print 'he is a Middle-aged people!'
   else:
      print 'he is a old people!'
except:
   print 'please value a integer!'

登录打招呼

user_name = ['admin', 'jack', 'bob', 'tom', 'mary']
for value in user_name:
   value = raw_input('please value a user name:')
   if value == 'admin':
      print 'hello %s, would you like to see a status report?'% value
      break
   elif value not in user_name:
      print 'error value'
      break
   else:
      print 'hello %s, thank you for logging in again' % value
      break

lists = [1,2,3,4,5,6,7,8,9]
for i in lists:
   if i == 1:
      print str(i) + 'st'
   elif i == 2:
      print str(i) + 'nd'
   elif i == 3:
      print str(i) + 'rd'
   else:
      print str(i) + 'th'