regex opltional matching groups

Question

Hi im trying to create a regex for the following expression

I need matching groups on all the integers

• Valid
  • integer-integer
  • integer-integer/integer
• Invalid
  • integer-integer/

So the first part would be like

^(\d+)-(\d+)

which matches 1-50

With these matching groups

• 1st group: 1
• 2nd group: 50

what do i need to add to the second part to make

/integer

optional but / should not be in the 3rd matching group and an integer is supplied

Answer 1

Put the slash inside a non-capturing group, and the number after it in a capture group.

^(\d+)-(\d+)(?:/(\d+))?

Answer 2

Use a non-capturing optional group, and inside it the integer group.

This should work for you:

^(\d+)-(\d+)(?:/(\d+))?$