切片是Python中用于获取序列(如字符串、列表、元组等)中的一部分的方法。 string="Python is great!"last_two_characters=string[-2:]print(last_two_characters) 1. 2. 3. 在上面的代码中,我们定义了一个字符串string,然后使用[-2:]来获取字符串的最后两个字符。这里负数索引表示从字符串末尾开始计数。 完...
String__getitem__() 在上面的类图中,String类表示字符串对象,该类包含了__getitem__()方法,用于获取字符串的切片。 完整示例代码 下面是一个完整的示例代码,展示了如何使用Python对字符串的最后两个值进行切割: defget_last_two_characters(s):returns[-2:]# 测试代码s="Hello, world!"substring=get_last_...
Write a Python program to get a string made of the first 2 and last 2 characters of a given string. If the string length is less than 2, return the empty string instead. Sample Solution: Python Code: # Define a function named string_both_ends that takes one argument, 'str'.defstring...
test="Python Programming"print("String: ",test)# First one character first_character=test[:1]print("First Character: ",first_character)# Last one character last_character=test[-1:]print("Last Character: ",last_character)# Everything except the first one character except_first=test[1:]print...
7 8 Public module variables: 9 10 whitespace -- a string containing all characters considered whitespace 11 lowercase -- a string containing all characters considered lowercase letters 12 uppercase -- a string containing all characters considered uppercase letters 13 letters -- a string containing ...
>>> achar = 'a' # string containing a single character >>> type(achar) <class 'str'> >>> >>> type("a string") # string containing multiple characters <class 'str'> >>> 使用len()函数计算字符数# 在len()内置函数计算字符串中的字符数。
word[4:]# Characters from position 4 (included) to the end. 输出为: Output 'on' 此示例显示在开始位置使用负索引: Python word[-2:]# Characters from the second-to-last (included) to the end. 输出为: Output 'on' 该特征表示s[:i] + s[i:]始终等于s,如下所示: ...
Last update on December 11 2024 09:20:06 (UTC/GMT +8 hours) Python Basic: Exercise-23 with Solution String Prefix Copies Write a Python program to get n (non-negative integer) copies of the first 2 characters of a given string. Return n copies of the whole string if the length is ...
>>> word[-2:] # characters from the second-last (included) to the end 'on'One way to remember how slices work is to think of the indices as pointing between characters, with the left edge of the first character numbered 0. Then the right edge of the last character of a string of...
But in Python 3, a string is always what Python 2 called a Unicode string — that is, an array of Unicode characters (of possibly varying byte lengths). Since this regular expression is defined by a string pattern, it can only be used to search a string — again, an array of ...