tell me the algorithm for splitting a number into digits in various ways without rearranging.

I know that depending on the length of the number, 2 ^ (N-1) options are obtained, where N is the length of the number . For example number 1234: (then 2^(4)= 8 )

1. [1234]
2. [1] [2] [3] [4]
3. [1] [2] [34]
4. [1] [23] [4]
5. [1] [234]
6. [12] [3] [4]
7. [12] [34]
8. [123] [4]

Recursion will not work, probably because I need to save these options.