/random with multiple ranges?

I want to randomly generate numbers from multiple ranges; /random 1..3, 7..9 and it will give any of: 1,2,3,7,8,9 Only two ranges seems easy: /store [...] random 1..2 if [...] 1 run random 1..3 if [...] 2 run random 7..9 Doing that for a very large amount of ranges is going to be really annoying though, is there a better way?