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#[allow(unused_imports)]
use std::cmp::*;
#[allow(unused_imports)]
use std::collections::*;
use std::io::Read;
#[allow(dead_code)]
fn getline() -> String {
let mut ret = String::new();
std::io::stdin().read_line(&mut ret).ok().unwrap();
ret
}
fn get_word() -> String {
let mut stdin = std::io::stdin();
let mut u8b: [u8; 1] = [0];
loop {
let mut buf: Vec<u8> = Vec::with_capacity(16);
loop {
let res = stdin.read(&mut u8b);
if res.unwrap_or(0) == 0 || u8b[0] <= b' ' {
break;
} else {
buf.push(u8b[0]);
}
}
if buf.len() >= 1 {
let ret = String::from_utf8(buf).unwrap();
return ret;
}
}
}
#[allow(dead_code)]
fn get<T: std::str::FromStr>() -> T { get_word().parse().ok().unwrap() }
/**
* p is prime
*/
fn modsqrt(mut a: i64, p: i64) -> Option<i64> {
a %= p;
if a == 0 {
return Some(0);
}
if p == 2 {
return Some(a);
}
if powmod(a, (p - 1) / 2, p) != 1 {
return None;
}
let mut b = 1;
while powmod(b, (p - 1) / 2, p) == 1 {
b += 1;
}
let mut e = 0;
let mut m = p - 1;
while m % 2 == 0 {
m /= 2;
e += 1;
}
let mut x = powmod(a, (m - 1) / 2, p);
let mut y = a * (x * x % p) % p;
x = x * a % p;
let mut z = powmod(b, m, p);
while y != 1 {
let mut j = 0;
let mut t = y;
while t != 1 {
j += 1;
t = t * t % p;
}
assert!(j < e);
z = powmod(z, 1 << (e - j - 1), p);
x = x * z % p;
z = z * z % p;
y = y * z % p;
e = j;
}
Some(x)
}
fn powmod(x: i64, mut e: i64, m: i64) -> i64 {
let mut sum = 1;
let mut cur = x % m;
while e > 0 {
if e % 2 != 0 {
sum = sum * cur % m;
}
cur = cur * cur % m;
e /= 2;
}
sum
}
fn solve() {
let p: i64 = get();
let r: i64 = get();
let q = get();
for _ in 0 .. q {
let a: i64 = get();
let b: i64 = get();
let c: i64 = get();
let b = b * powmod(a, p - 2, p) % p;
let c = c * powmod(a, p - 2, p) % p;
let ss = modsqrt((b * b + (2 * p - 4) * c) % p, p);
match ss {
Some(ss) => {
let mut hs = Vec::new();
hs.push(((2 * p - b - ss) % p) * powmod(2, p - 2, p) % p);
hs.push(((p - b + ss) % p) * powmod(2, p - 2, p) % p);
hs.sort();
if hs[0] == hs[1] {
println!("{}", hs[0]);
} else {
println!("{} {}", hs[0], hs[1]);
}
},
None => {
println!("-1");
},
}
}
}
fn main() {
// In order to avoid potential stack overflow, spawn a new thread.
let stack_size = 104_857_600; // 100 MB
let thd = std::thread::Builder::new().stack_size(stack_size);
thd.spawn(|| solve()).unwrap().join().unwrap();
}
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