In Python, you can use string slicing to obtain substrings in a string. The basic syntax of string slicing is "substring = string[start:end:step]".
The operating system for this tutorial: Windows 10 system, Python version 3.11.4, Dell G3 computer.
In Python, you can use string slicing to obtain substrings in a string. The basic syntax of string slicing is as follows:
substring = string[start:end:step]
string is the string to be sliced.
start is the starting index, indicating the starting position to slice (including the characters at this position).
end is the end index, indicating the end position of the slice (not including the characters at this position).
step is the step size, indicating how many characters to slice every time, the default is 1.
Here are some examples:
s = "Hello, World!" print(s[7:]) # 从索引 7 开始到结尾的子串 print(s[:5]) # 从开头到索引 5(不包含索引 5)的子串 print(s[7:12]) # 从索引 7 到索引 12(不包含索引 12)的子串 print(s[::2]) # 从开头到结尾,每隔一个字符取一个字符 print(s[::-1]) # 逆序输出整个字符串
In these examples, different starting index, ending index and step size are used to get substrings of strings. It should be noted that the index starts from 0, and the slicing operation is a left-closed and right-open interval, which includes the starting index but not the ending index.
By flexibly using string slicing, you can easily obtain substrings in a string to meet various needs.
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