# Problem #5

Discrete Mathematics Level 3

How many '1's appear in the following number:

$12345678910111213141516...9999989999991000000?$

It is formed by joining the integers from 1 to 1000000 back-to-back and in order. You should be able to see the ? question mark at the back of the number.

This problem is part of the set Easy Problems

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