### You can read a string backwards with the following syntax:# string[::-1] - where the "-1" means one step back.# This exercise can be solved with only unit 1 knowledge# (no loops or conditions)word ="madman"# test case 2# word = "madman" # uncomment this to test### YOUR...
We have a string, "Hello World", which we want to reverse: The String to Reverse txt ="Hello World"[::-1] print(txt) Create a slice that starts at the end of the string, and moves backwards. In this particular example, the slice statement[::-1]means start at the end of the st...
normal_list = [1, 2, 3, 4, 5]class CustomSequence:def __len__(self):return 5def __getitem__(self, index):return f"x{index}"class FunkyBackwards:def __reversed__(self):return "BACKWARDS!"for seq in normal_list, CustomSequence(), FunkyBackwards():print(f"\n{seq.__class__.__...
Recursion. Rewrite your solution to Exercise 6-5, which prints a string backwards to use recursion. Use recursion to print a string forward and backward. 【答案】 代码如下:#-*- encoding: utf-8 -*- def Rprint(n, string): print string.pop(0), #当参数为0时,顺序输出字符串。当参数为默...
这段代码之所以有效,是因为循环将来迭代的所有项的索引都没有改变。但是在删除的值之后,值的重复上移使得这种技术对于长列表来说效率很低。这段代码的可视化执行在autbor.com/iteratebackwards1进行。你可以在图 8-3 中看到向前迭代和向后迭代的区别。
>>> sys.getsizeof('a much longer string than just "cat"') 85 (在我使用的 Python 版本中,string 对象的开销占用 49 个字节,而字符串中的每个实际字符占用 1 个字节。)但是包含这些字符串中任何一个的列表都要占用 72 个字节,不管字符串有多长: ...
(5) See what has been printed up to this step. Here the print statement in theNodeconstructor (line 5) has run 3 times. The user can navigate forwards and backwards through all execution steps, and the visualization changes to match the run-time state of the stack and heap at each step...
If the ordering requirement is to order an iterable by each string spelled backwards, then you could define a function that reverses a word. In the example below, you define a function named reverse_word() that reverses the string passed to it. Then, you use reverse_word as the value of...
# it'll loop through the string backwards return str[::-1] print (FirstReverse(input())) 非常简洁str[::-1]就可以完成目标。 三、切片详解 1、取字符串中第几个字符 >>> 'hello'[0]#表示输出字符串中第一个字符 'h' >>> 'hello'[-1]#表示输出字符串中最后一个字符 ...
print sys.path 结果: ['/Users/wupeiqi/PycharmProjects/calculator/p1/pp1', '/usr/local/lib/python2.7/site-packages/setuptools-15.2-py2.7.egg', '/usr/local/lib/python2.7/site-packages/distribute-0.6.28-py2.7.egg', '/usr/local/lib/python2.7/site-packages/MySQL_python-1.2.4b4-py2.7-macosx...