Python基础二：条件和循环

1. if else

   1     str = "a"
   2     if str == "a":
   3         print "a"
   4     else:
   5         print "b"

2. if elif else

   1     score = 70
   2     if score > 90:
   3         print ">90"
   4     elif score > 70:
   5         print ">70"
   6     elif score >= 60:
   7         print ">=60"
   8     else:
   9         print "<60"

3. 不支持switch

• while

  1     count = 0
  2     while(count < 9):
  3         print "The count is:", count
  4         count = count + 1
  5     print "Good bye!"

• while else

  1     count = 0
  2     while count < 5:
  3        print count, " is  less than 5"
  4        count = count + 1
  5     else:
  6        print count, " is not less than 5"

• for & for else:    else 中的语句会在循环正常执行完（即 for 不是通过 break 跳出而中断的）的情况下执行
• • 
• 关键字 continue ,break 同其他语言
• pass 空语句，为了保持程序结构的完整性，作为占位语句

  1     tmp = ‘y‘
  2     if tmp == ‘y‘:
  3         pass
  4     else:
  5         print ‘x‘

   

Python基础二：条件和循环

原文：http://www.cnblogs.com/nightcatcher/p/6505893.html