Problem:
Score : 200 points

Problem Statement

Find the sum of the integers between 1 and N (inclusive), whose sum of digits written in base 10 is between A and B (inclusive).

Constraints

1 \leq N \leq 10^4

1 \leq A \leq B \leq 36

All input values are integers.

Input

Input is given from Standard Input in the following format:

N A B

Output

Print the sum of the integers between 1 and N (inclusive), whose sum of digits written in base 10 is between A and B (inclusive).

Sample Input 1

20 2 5

Sample Output 1

84

Among the integers not greater than 20, the ones whose sums of digits are between 2 and 5, are: 2,3,4,5,11,12,13,14 and 20. We should print the sum of these, 84.

Sample Input 2

10 1 2

Sample Output 2

13

Sample Input 3

100 4 16

Sample Output 3

4554

Solution in Ruby (2.3.3) (judge verdict: Accepted)

N,A,B = gets.split(" ").map(&:to_i)

nums = (0..N).to_a
sums = 0

nums.each do |n|
  one = n%10
  ten = (n/10)%10
  hundred = (n/100)%10
  thousand = (n/1000)%10
  t_thousand = (n/10000)%10
  sum = one + ten + hundred + thousand + t_thousand
  sums += n if A <= sum && sum <= B
end

puts sums