Сумма цифр

use std::io;
use std::str::SplitWhitespace;

fn sum_num_ultra(mut x: i128) -> i128 {
    let mut sum: i128 = 0;
    while x > 0 {
        sum += x % 10;
        x /= 10;
    }
    return sum;
} /*общий поиск суммы цифр*/

fn main() {
    let mut t: String = String::new();
    io::stdin().read_line(&mut t).unwrap();
    let t: usize = t.trim().parse().unwrap();
    let mut v: Vec<(u32, u32)> = Vec::with_capacity(t);
    v.resize(t, (0, 0));
    for i in 0..t {
        let mut input: String = String::new();
        io::stdin().read_line(&mut input).unwrap();
        let mut it_input: SplitWhitespace = input.split_whitespace();
        let num: u32 = it_input.next().unwrap().parse().unwrap();
        let amn: u32 = it_input.next().unwrap().parse().unwrap();
        v[i].0 = num;
        v[i].1 = amn;
    }
    let mut answer: Vec<i128> = Vec::with_capacity(t);
    for i in v.iter() {
        if i.1 == 0 {
            let mut count: usize = 0;
            let mut target: u32 = i.0;
            while target >= 9 {
                target -= 9;
                count += 1;
            }
            let mut str: String = String::with_capacity(count + 1);
            if target > 0 {
                str.push(std::char::from_digit(target, 10).unwrap());
            }
            for _q in 0..count {
                str.push(std::char::from_digit(9, 10).unwrap());
            }
            answer.push(str.trim().parse().unwrap());
        } else {
            let mut print: bool = false;
            let mut min: i128 = 69999999999999999;
            for x in 0..10 {
                let mut pred: i128 = sum_num_ultra(x);
                let mut sum: i128 = pred;
                for q in x + 1..x + i.1 as i128 + 1 {
                    if q % 10 != 0 {
                        sum += pred + 1;
                        pred += 1;
                    } else {
                        pred = sum_num_ultra(q);
                        sum += pred;
                    }
                }
                if sum == i.0 as i128 {
                    if x < min {
                        min = x;
                    }
                    print = true;
                } else if sum < i.0 as i128 {
                    let mut target: i128 = i.0 as i128;
                    target -= sum;
                    let mut ur: i128 = 0;
                    let mut nine: bool = false;
                    for b in x..x + i.1 as i128 + 1 {
                        if nine {
                            ur += 1;
                        }
                        if b % 10 == 9 {
                            nine = true;
                        }
                    }
                    target -= ur;
                    if target >= 0 && target % (i.1 as i128 + 1) == 0 {
                        let mut cif: i128 = target / (i.1 as i128 + 1);
                        let mut an: String = String::with_capacity(cif as usize / 9 + 1);
                        an.push(std::char::from_digit(x as u32, 10).unwrap());
                        while cif >= 9 {
                            cif -= 9;
                            an.insert(0, '9');
                        }
                        if cif > 0 {
                            an.insert(0, std::char::from_digit(cif as u32, 10).unwrap());
                        }
                        let a: i128 = an.trim().parse().unwrap();
                        if a < min {
                            min = a;
                        }
                        print = true;
                    }
                }
            }
            if !print {
                answer.push(-1);
            } else {
                answer.push(min);
            }
        }
    }
    for i in answer {
        println!("{}", i);
    }
}