# Digital sum

The digital root of a number is obtained by adding together the digits of that number, and repeating that process until a number is arrived at that is less than $$10$$.

For example,for $$29953$$ the digital root is $$29953 \rightarrow 28\rightarrow 10\rightarrow 1$$.

Let $$S$$ be the number of all positive integers less than one million that have a digital root of $$1$$. What is the digital root of $$S$$?

Check out part 2 for a more challenging version

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