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 C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Linq;

namespace ABC083
{
    class B
    {
        static void Main(string[] args)
        {
            var NAB = Console.ReadLine().Split(' ').Select(s => int.Parse(s)).ToArray();
            var N = NAB[0];
            var A = NAB[1];
            var B = NAB[2];
            var res = 0;
            for (int i = 1; i <= N; i++)
            {
                var n = i;
                var sum = n % 10;
                while ((n /= 10) != 0)
                    sum += n % 10;

                if (A <= sum && sum <= B) res += i;
            }
            Console.WriteLine(res);
        }
    }
}