How to form character sets that meet the requirements?

Question

Algorithms

There are 30 characters (26 characters of the Latin alphabet and numbers 1,2,3,4). It is necessary to form 30 sets of 6 characters each, satisfying the requirements:
1. all characters are randomly distributed
2. in one set of 6 characters, all characters are unique (that is, they do not repeat)
3. for each set of 6 characters, there is another set that has only 1 character matches
How can this be done via js?

Answer 1

1. Randomly choose 6 characters without repetitions from the main character set
   
2. Create an additional set consisting of the characters of the main minus 6 characters of the current set
   
3. Create a new set containing a random character from the current set
   
4. Declaring the new set current and adding 5 random non-repetitive characters from the additional set
   
5. goto 2