The sentence stating the problem is incorrect or incomplete: "Given ... , plus one to the number.". At the very least I would expect the word "return" in there somewhere. It would make even more sence if the problem explicitly stated that the goal is to "return the set of numbers, that .."
i have same sense that i don't understand the problem. what's the meaning of "the most significant digit" ?
In computing, the most significant bit (msb or MSB, also called the high-order bit) is the bit position in a binary number having the greatest value. The msb is sometimes referred to as the left-most bit due to the convention in positional notation of writing more significant digits further to the left.
Find out in wiki