DWITE Online Computer Programming Contest

C001 Numbers

October 2011
Problem 4

According to recent surveys run by various computer science clubs at Canadian high schools, 0 is a cool digit. That’s why we are going to define the “coolness” of a number to be the number of 0s it has (e.g. 100 has a coolness of 2, whereas 1 has no coolness). This makes counting a very cool activity, which raises the question: Exactly how cool is it to be able to count up to N? We are interested in finding the total coolness of all numbers from 0 up to a given number.

The input file DATA4.txt will contain 5 test cases, each being a line with a single number 0 ≤ N ≤ 10,000,000.

The output file OUT4.txt will contain 5 lines of output, the sum of the coolness of all the numbers from 0 to N inclusive.

Sample Input:
0
13
55
4
100
Sample Output:
1
2
6
1
12