Python快速入门（2）练习题

		def fix_start(s):
		  # +++your code here+++
		  # LAB(begin solution)
		  front = s[0]
		  back = s[1:]
		  fixed_back = back.replace(front, ‘*‘)
		  return front + fixed_back

# E. not_bad
# Given a string, find the first appearance of the
# substring ‘not‘ and ‘bad‘. If the ‘bad‘ follows
# the ‘not‘, replace the whole ‘not‘...‘bad‘ substring
# with ‘good‘.
# Return the resulting string.
# So ‘This dinner is not that bad!‘ yields:
# This dinner is good!

		def not_bad(s):
		  # +++your code here+++
		  # LAB(begin solution)
		  n = s.find(‘not‘)
		  b = s.find(‘bad‘)
		  if n != -1 and b != -1 and b > n:
			s = s[:n] + ‘good‘ + s[b+3:]
		  return s

Python快速入门（2）练习题

原文：http://blog.csdn.net/tao_sun/article/details/18743387