Question

how can i check for a pattern occuring a certain number of times?

eg:

4444444 => return 4

4444332 => return 4

4444431 => return 4

4443333 => return 0

4243424 => return ?

but if character 4 occurs less than 4 times then return 0

i am just looking for 4 here. if it appears more than or equal to 4 times then value returned would be 4. the other 3 numbers in the string can range from 1 to 3 only.

thank you.

Answer 1

If you need four consecutive 4s, it’s just 4{4} or 4444. If they don’t need to be consecutive, 4.*4.*4.*4 will do it. If it can be any number, but has to be four times, then ([1-4])\1{3} or ([1-4]).*\1.*\1.*\1 depending on whether you need them to be consecutive or not.