codecademy上过教程.练习中遇到了题述问题.且不能用reversed函数跟[::-1]
大家有什么好方法?
def rev(s):
r = list()
for c in s:
r.insert(0, c)
return ''.join(r)def reversed_index(n):
for i in range(n-1, -1, -1):
yield i
test_string = "我爱北京天安门"
new_string = ""
for i in reversed_index(len(test_string)):
new_string += test_string[i]
print(new_string)str = "hello world"
l = len(str)
for i in range(l):
print str[l - i - 1]双端队列
from collections import deque
def string_reverse(string):
d = deque()
d.extendleft(string)
return ''.join(d);
def reserveStr(s):
length = len(s)
result = ''
for i in range(length):
result += s[length - i - 1]
return result