Not able to not match substring and match string

Question

I am quite new to regular expressions and I have been strugling with finding the correct one for my need an it is the following: I need to get if the string starts with a "n" or a "p" and for that I have ^(n|p). Next up any three of combinations can happen and for that I have (fcombination|scombination|tcombination), after that it's where I problem start to rise. I need to match if "hvt" happens after previous conditions, but not if it's just "hv" other than "hv" any substring should be match.

Can any of the experts help?

Regards

Answer 1

If I understand what you're after, the regex ^[np][fst]combination(?!hv(?!t)).* would match

nfcombinationhvt  //match
pscombinationhvt  //match
ntcombinationhvt  //match
nfcombinationdrums  //match
pscombinationguitar  //match
ntcombinationkicker  //match
nfcombinationhvxxx  //no match
pscombinationhvzz  //no match
ntcombinationhva  //no match
nfcombinationhv  //no match
pscombinationhv  //no match
ntcombinationhv  //no match