如何修改正则表达式以支持Python的**、//运算符分割算术字符串？

开发者阿泽

2026-5-25

Got it, let's fix this to support Python's ** (exponentiation) and // (floor division) operators! The issue with your current regex is that it treats * and / as single-character tokens, so it splits ** into two separate *s and // into two /s. We need to adjust the regex to recognize these two-character operators as whole units first, then handle the single-character ones.

The Approach

The key idea is to:

Avoid splitting in the middle of ** or //
Add explicit split points before and after these two-character operators (without breaking them apart)
Keep supporting all your original single-character operators (=, +, -, *, /, %, (, ))

Updated Code

Here's the adjusted Java code with the modified regex:

String stringM = "variable1 = 1 + 2 ** (4 // (3 + 2) / 6)";
String str = stringM.replaceAll("\\s+", "");
// Regex updated to handle Python's ** and // operators
String[] result = str.split("(?<=[-+%=()])|(?=[-+%=()])|(?<!\\*)(?=\\*\\*)|(?<=\\*\\*)(?!\\*)|(?<!/)(?=//)|(?<=//)(?!/)");

Regex Breakdown

Let's unpack the new parts of the regex:

(?<=[-+%=()])|(?=[-+%=()]): Your original logic for single-character operators (we excluded * and / here to handle them separately)
(?<!\\*)(?=\\*\\*): Matches the position right before ** (ensures the previous character isn't another *, so we don't split in the middle of existing *s)
(?<=\\*\\*)(?!\\*): Matches the position right after ** (ensures the next character isn't another *)
(?<!/)(?=//): Matches the position right before // (previous character isn't /)
(?<=//)(?!/): Matches the position right after // (next character isn't /)