What are the regular expressions for integers?

The regular expressions for integers are: 1. Match positive integers: ^[1-9]\d*$; 2. Match negative integers: ^-[1-9]\d*$; 3. Match positive and negative integers: ^-?\d $; 4. Match non-zero integers: ^(0|[1-9]\d*)$; 5. Match integers (including zero): ^-?\d $.

Operating system for this tutorial: Windows 10 system, Dell G3 computer.

Regular Expression (Regular Expression) is a powerful text processing tool that can match, search, replace or split complex string patterns.

The following are some regular expressions that match integers (positive and negative integers):

1. Match positive integers:

^[1-9]\d*$

This regular expression matches any from 1 Starting at 9, followed by a string of any number of digits.

2. Match negative integers:

^-[1-9]\d*$

This regular expression matches any string starting with a negative sign (-), followed by a number from 1 to 9, and then followed by any number of digits .

3. Match positive and negative integers:

^-?\d+$

This regular expression matches any integer that may have a negative sign. If the string is preceded by a negative sign, the match is negative, otherwise it is positive or zero.

4. Match non-zero integers:

^(0|[1-9]\d*)$

This regular expression matches any non-zero integer, including positive integers and negative integers. If the string is zero, it will also be matched.

5. Match integers (including zero):

^-?\d+$

This regular expression matches any integer, including zero. If the string is preceded by a negative sign, the match is negative, otherwise it is positive or zero.

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