How do i generate all possible subsets of an binary string?

Question

i have a problem, that i don\'t know how to solve it.

i have a binary string and i want to generate all possible binary substrings.

Example :

Answer 1

1. If you just want values that are below the numeric value of the binary string, keep taking one away from the binary string until you get to 0.
2. If you want all values that can be represented by that number of binary digits, subtract 1 from the highest number that can be represented by that number of digits until you get to 0.

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