Python實現(xiàn)單詞反轉效果

import re

def reserve(str_list, start, end):
 while start <= end:
 str_list[start], str_list[end] = str_list[end], str_list[start]
 end -= 1
 start += 1

str = ' I love china! '
str_list = list(str)
print(str_list)
i = 0
print(len(str_list))

# 從前往后遍歷list，如果碰到空格，就調用反轉函數(shù)，不考慮單個字符情況
while i < len(str_list):
 if str_list[i] != ' ':
 start = i
 end = start + 1
 print(end)
 while (end < len(str_list)) and (str_list[end]!=' '):
 end += 1
 if end - start > 1:
 reserve(str_list, start, end-1)
 i = end
 else:
 i = end
 else:
 i += 1

print(str_list)
str_list.reverse()
print(''.join(str_list))

# 采用正則表達式操作
str_re = re.split(r'(s+)',str)

str_re.reverse()
str_re = ''.join(str_re)
print(str_re)