Regex - find word in string

Question

I have a string: prawy p pęknięty p zderzak pęknięcie (it's Polish language)

I want to select all p (except "p" in words "pęknięty" and "peknięcie")

I've tried to do something like that: \b(s*ps*)\b, but it doesn't work properly. Any ideas?

Answer 1

Maybe,

\bp(?=[a-z]+|\s|$)

or

(?!pęknięcie|pęknięty)\bp

might simply work fine.

Demo 1

Demo 2

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RegEx Circuit

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Answer 2

You might use a negative lookahead and a character class:

\bp(?!([eę]knię(?:cie|ty)\b)

In parts

• \bp preceded by a word boundary
• (?! If what is directly on the right is not
  • [eę]knię Match e or ę followed by knię
  • (?:cie|ty)\b Match cie or ty and a word boundary
• ) Close negative lookahead

Regex demo

Using a character class might match an invalid variation of e or ę in the words.

To match the words exactly you could match them between word boundaries

\bp(?!ęknięty\b|ęknięcie\b)

Regex demo