How to achieve minimum matching with python regular expressions

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Minimum matching

Format:

Quantifier?

Note: the quantifiers are {nMagol m},?, +, *

Use:

Find the shortest substring in a string that meets the regular expression rules.

Case study:

The existing string num = "10-3 * (20-10 + (- 10 + (- 10-5)) 27-max) 3-(- 100) / (10-35)", to extract the contents in parentheses.

Import renum ='10-3 * (20-10 + (- 10 +) / (10-3) + (- 5) num2 6) 'num2 = re.findall ('\ (. +?\), num) num3 = re.findall ('(. +\)', num) print (num2) print (num3) out: ['(20-10 + (- 10 + 5)','(- 100)' '(10-3-5)'] [(20-10 + (- 10-10) 5) * 27-3) 3-(- 100) / (10-3-5))']

In the above code, num2 uses the minimum match, while num3 uses the default maximum match.

Notice the regular expression of num2:

. Indicates that all characters except newline characters are matched

+ represents one or more

? Represents the minimum match, followed by the first match), which returns the result. Without this? Will match to the last) before the result is returned.

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