# Can you find the digit?

$S=123456789101112131415161718192021\ldots$

Given that the string $$S$$ is the concatenation of the first 1,000,000,000 positive integers in ascending order, find the $$999999999^{\text{th}}$$ digit of $$S$$.

Details and Assumptions:

By the $$x^{\text{th}}$$ digit of $$S$$, we mean the digit in the $$x^{\text{th}}$$ place from the left in the decimal representation of $$S$$.

Some explicit examples are :

• The $$5^{\text{th}}$$ digit of the number $$14583469$$ is $$3$$.
• The $$4^{\text{th}}$$ digit of the number $$143256$$ is $$2$$.
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