Problem:
Score : 600 points

Problem Statement

Consider the following arithmetic progression with n terms:

x, x + d, x + 2d, \ldots, x + (n-1)d

What is the product of all terms in this sequence?
Compute the answer modulo 1\ 000\ 003.

You are given Q queries of this form.
In the i-th query, compute the answer in case x = x_i, d = d_i, n = n_i.

Constraints

1 \leq Q \leq 10^5

0 \leq x_i, d_i \leq 1\ 000\ 002

1 \leq n_i \leq 10^9

All values in input are integers.

Input

Input is given from Standard Input in the following format:

Q
x_1 d_1 n_1
:
x_Q d_Q n_Q

Output

Print Q lines.

In the i-th line, print the answer for the i-th query.

Sample Input 1

2
7 2 4
12345 67890 2019

Sample Output 1

9009
916936

For the first query, the answer is 7 \times 9 \times 11 \times 13 = 9009.
Don't forget to compute the answer modulo 1\ 000\ 003.

Solution in Rust (1.15.1) (judge verdict: Accepted)

#![allow(unused_imports)]
#![allow(non_snake_case)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let q = read::<usize>();
    let big_int = 1000_003;
    let fact = ModFactorial::new(1000_002, big_int).fact;
    for i in 0..q {
        let v = read_vec::<i64>();
        let (x, d, n) = (v[0], v[1], v[2]);
        let x_d = (x * mod_inverse(d, big_int)) % big_int;
        if d == 0 {
            println!("{}", pow_m(x, n, big_int));
        } else {
            let large_idx = (n + x_d - 1) as usize;
            let small_idx = (x_d - 1) as usize;
            if large_idx >= big_int as usize || large_idx == 0 {
                println!("0");
                continue;
            }
            let mut temp = fact[large_idx] * mod_inverse(fact[small_idx], big_int);
            temp %= big_int;
            temp *= pow_m(d, n, big_int);
            temp %= big_int;
            println!("{}", temp);
        }
    }
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}

fn pow_m(n: i64, mut p: i64, m: i64) -> i64 {
    let mut r = n;
    let mut ret = 1;
    while p > 0 {
        if p % 2 == 0 {
            r = r * r % m;
            p /= 2;
        } else {
            ret = ret * r % m;
            p -= 1;
        }
    }
    ret
}

fn extgcd(a: i64, b: i64, x: &mut i64, y: &mut i64) -> i64 {
    let mut d = a;
    if b == 0 {
        *x = 1;
        *y = 0;
    } else {
        d = extgcd(b, a % b, y, x);
        *y -= (a / b) * (*x);
    }
    return d;
}

fn mod_inverse(a: i64, m: i64) -> i64 {
    let mut x: i64 = 0;
    let mut y: i64 = 0;
    extgcd(a, m, &mut x, &mut y);
    (m + x % m) % m
}

struct ModFactorial {
    fact: Vec<i64>,
}

// returns n! under mod m
impl ModFactorial {
    fn new(n: i64, m: i64) -> ModFactorial {
        let mut fact = vec![1; n as usize + 1];
        for i in 2..fact.len() {
            fact[i] = (i as i64 * fact[i - 1]) % m;
        }
        ModFactorial { fact: fact }
    }
}