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 Pascal (FPC 2.6.2) (judge verdict: Accepted)

var
    a,b,c,i,j,z:longint;
    s:array[1..10000]of string;
    k:array[1..10000]of longint;
    ans:qword;
begin
    read(a,b,c);
    for i:=1 to a do
    begin
        str(i,s[i]);
        for j:=1 to length(s[i]) do
        begin
            val(s[i][j],z);
            k[i]:=k[i]+z;
        end;
        if(k[i]>=b)and(k[i]<=c)then inc(ans,i);
    end;
    writeln(ans);
end.