Question 25
Let the number of odd digits of a positive integer $n$ be denoted as $O_{(n)}$ and the number of even digits be denoted as $E_{(n)}$. For example, $O_{(13)}=2$ and $E_{(58)}=1$. What is the numerical value of $O_{(1)}-E_{(2)}+O_{(3)}-E_{(4)}+\cdots+O_{(201)}-E_{(202)}$?
(Note: 0 is even digit)
(Note: 0 is even digit)