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 Rust (1.15.1) (judge verdict: Accepted)

use std::io;

fn read_line() -> String {
    let mut s = String::new();
    io::stdin().read_line(&mut s).unwrap();
    s
}

macro_rules! from_line {
    ($($a:ident : $t:ty),+) => {
        $(let $a: $t;)+
        {
            let _line = read_line();
            let mut _it = _line.trim().split_whitespace();
            $($a = _it.next().unwrap().parse().unwrap();)+
                assert!(_it.next().is_none());
        }
    };
}

fn digit_sum(n: i64) -> i64 {
    let mut sum = 0;
    let mut tmp_n = n;

    loop {
        sum += tmp_n % 10;
        tmp_n = tmp_n / 10;

        if tmp_n == 0 {
            break;
        }
    }
    sum
}

fn main() {
    from_line!(n: i64, a: i64, b: i64);
    let mut sum = 0;
    for i in 1..n+1 {
        if a <= digit_sum(i) && digit_sum(i) <= b {
            sum += i;
        }
    }
    println!("{}", sum);
}