I'm trying to find a unique number from string which contain 4 numbers seprated by spaces in between them (not at start & end) & occurrence of these numbers should be 3.
I've tried like this but it gives me numbers with & without spaces which I don't want it should contain spaces in between them.
Example
(\d{4}.?){3}
above regex selects these as correct
2131 2312 367521312312123136752131 1231 3675- (this includes spaces at start & end)
In option (3) I can ignore spaces but I don't want output as option (2).
How can I fix this?
Live example