結果
| 問題 | No.3768 Sum of Difference of XOR |
| コンテスト | |
| ユーザー |
akakimidori
|
| 提出日時 | 2026-10-17 01:07:00 |
| 言語 | Rust (1.99.0 + proconio + num + itertools + ACL) |
| 結果 |
AC
不安定
|
| 実行時間 | 2,095 ms / 4,000 ms |
| + 135µs | |
| コード長 | 24,804 bytes |
| 記録 | |
| コンパイル時間 | 13,320 ms |
| コンパイル使用メモリ | 205,920 KB |
| 実行使用メモリ | 13,812 KB |
| 最終ジャッジ日時 | 2026-10-17 01:07:52 |
| 合計ジャッジ時間 | 46,781 ms |
|
ジャッジサーバーID (参考情報) |
judge5_0 / judge1_0 |
(要ログイン)
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 21 |
コンパイルメッセージ
warning: unused import: `std::io::Write`
--> src/main.rs:2:5
|
2 | use std::io::Write;
| ^^^^^^^^^^^^^^
|
= note: `#[warn(unused_imports)]` (part of `#[warn(unused)]`) on by default
warning: unused variable: `i`
--> src/main.rs:83:10
|
83 | for (i, (a, b)) in [(&a, &b), (&b, &a)].iter().enumerate() {
| ^ help: if this is intentional, prefix it with an underscore: `_i`
|
= note: `#[warn(unused_variables)]` (part of `#[warn(unused)]`) on by default
warning: variable does not need to be mutable
--> src/main.rs:129:9
|
129 | let mut p = a.iter().fold(M::zero(), |s, a| s + *a);
| ----^
| |
| help: remove this `mut`
|
= note: `#[warn(unused_mut)]` (part of `#[warn(unused)]`) on by default
warning: variable does not need to be mutable
--> src/main.rs:130:9
|
130 | let mut q = c.iter().fold(M::zero(), |s, a| s + *a);
| ----^
| |
| help: remove this `mut`
warning: variable does not need to be mutable
--> src/main.rs:131:9
|
131 | let mut x = xor_conv(a, b, pc);
| ----^
| |
| help: remove this `mut`
warning: variable does not need to be mutable
--> src/main.rs:132:9
|
132 | let mut y = xor_conv(c, b, pc);
| ----^
| |
| help: remove this `mut`
warning: unused variable: `pc`
--> src/main.rs:147:31
|
147 | fn xor_conv(a: &[M], b: &[M], pc: &Precalc<998244353>) -> Vec<M> {
| ^^ help: if this is intentional, prefix it with an underscore: `_pc`
warning: type alias `Map` is never used
--> src/main.rs:4:6
|
4 | type Map<K, V> = BTreeMap<K, V>;
| ^^^
|
= note: `#[warn(dead_code)]` (part of `#[warn(unused)]`) on by default
warning: type alias `Set` is never used
--> src/main.rs:5:6
|
5 | type Set<T> = BTreeSet<T>;
| ^^^
warning: type alias `Deque` is never used
--> src/main.rs:6:6
ソースコード
use std::collections::*;
use std::io::Write;
type Map<K, V> = BTreeMap<K, V>;
type Set<T> = BTreeSet<T>;
type Deque<T> = VecDeque<T>;
fn main() {
input! {
n: usize,
a: [usize; n],
}
let w = 18;
let pc = Precalc::new(n + (1 << w));
//let a = (0..n).map(|_| rand() % (1 << w)).collect::<Vec<_>>();
let mut b = vec![M::zero(); 1 << w];
for a in a {
b[a] += M::one();
}
let ans = dfs(&b, w, &pc);
println!("{}", ans);
// println!("{:?}", efs(vec![M::zero(), M::zero(), M::one(), M::one()], vec![M::zero(), M::one(), M::zero(), M::one()], 2));
}
fn dfs(a: &[M], w: usize, pc: &Precalc<998244353>) -> M {
if w == 0 || a.iter().fold(M::zero(), |s, a| s + *a).get() < 4 {
return M::zero();
}
let w = w - 1;
let (l, r) = a.split_at(1 << w);
let mut ans = dfs(l, w, pc) + dfs(r, w, pc);
let (a, b) = (l, r);
// 22
//println!("check 22: {:?} {:?}", a, b);
let mut c = xor_conv(a, a, pc);
let mut d = xor_conv(b, b, pc);
c[0] -= a.iter().fold(M::zero(), |s, a| s + *a);
d[0] -= b.iter().fold(M::zero(), |s, a| s + *a);
let mut sum = M::zero();
let mut way = M::zero();
for (i, d) in d.iter().enumerate() {
sum += M::from(i) * *d;
way += *d;
}
let mut ls = M::zero();
let mut lw = M::zero();
let mut add = M::zero();
for (i, c) in c.iter().enumerate() {
add += *c * sum;
add -= *c * way * M::from(i);
add += *c * lw * M::from(i);
add -= *c * ls;
sum -= M::from(i) * d[i];
way -= d[i];
ls += M::from(i) * d[i];
lw += d[i];
}
//println!("22: {}", add);
ans += add * M::new(2);
// 22, 11 11
let lr = xor_conv(a, b, pc);
let mut sum = M::zero();
let mut way = M::zero();
let mut add = M::zero();
for (i, lr) in lr.iter().enumerate() {
add += *lr * way * M::from(i);
add -= *lr * sum;
sum += *lr * M::from(i);
way += *lr;
}
add *= M::new(8);
add -= efs(a, b, w, pc) * M::new(8);
add -= efs(b, a, w, pc) * M::new(8);
//println!("22, 1111: {:?} {:?} {}", a, b, add);
ans += add;
add = M::zero();
// 1,3 or 3, 1
//println!("check 13, {:?} {:?}", a, b);
for (i, (a, b)) in [(&a, &b), (&b, &a)].iter().enumerate() {
let s = b.iter().fold(M::zero(), |s, a| s + *a);
let ab = xor_conv(a, b, pc);
let bb = xor_conv(b, b, pc);
let p = ab.iter().fold(M::zero(), |s, a| s + *a);
let q = bb.iter().fold(M::zero(), |s, a| s + *a);
for (i, (x, y)) in ab.iter().zip(bb.iter()).enumerate() {
add += *x * M::from(i + (1 << w)) * q;
add -= *y * M::from(i) * p;
}
add -= s * ab
.iter()
.enumerate()
.fold(M::zero(), |s, (i, a)| s + M::from(i + (1 << w)) * *a);
add -= M::new(2) * sub(b, a, b, pc);
add += ab
.iter()
.enumerate()
.fold(M::zero(), |s, (i, a)| s + M::from(i + (1 << w)) * *a)
* M::new(3);
add -= ab
.iter()
.enumerate()
.fold(M::zero(), |s, (i, a)| s + M::from(i + (1 << w)) * *a);
}
//println!("{}", add);
ans += add * M::new(4);
ans
}
fn efs(a: &[M], b: &[M], w: usize, pc: &Precalc<998244353>) -> M {
if w == 0 || a.iter().all(|a| a.is_zero()) || b.iter().all(|b| b.is_zero()) {
return M::zero();
}
let w = w - 1;
let (a, c) = a.split_at(1 << w);
let (b, d) = b.split_at(1 << w);
let v = b.add(d);
let mut ans = efs(a, &v, w, pc) + efs(c, &v, w, pc);
ans += sub(a, c, b, pc);
ans += sub(c, a, d, pc);
ans
}
fn sub(a: &[M], c: &[M], b: &[M], pc: &Precalc<998244353>) -> M {
let mut ans = M::zero();
let mut p = a.iter().fold(M::zero(), |s, a| s + *a);
let mut q = c.iter().fold(M::zero(), |s, a| s + *a);
let mut x = xor_conv(a, b, pc);
let mut y = xor_conv(c, b, pc);
let w = a.len();
ans += (0..w)
.map(|i| M::from(i + w) * y[i])
.fold(M::zero(), |s, a| s + a)
* p;
ans -= (0..w)
.map(|i| M::from(i) * x[i])
.fold(M::zero(), |s, a| s + a)
* q;
ans
}
type M = ModInt<998244353>;
fn xor_conv(a: &[M], b: &[M], pc: &Precalc<998244353>) -> Vec<M> {
if a.len() <= 4 {
let mut res = vec![M::zero(); a.len()];
for (i, a) in a.iter().enumerate() {
for (j, b) in b.iter().enumerate() {
res[i ^ j] += *a * *b;
}
}
return res;
}
let mut a = Vec::from(a);
let mut b = Vec::from(b);
fwht(&mut a);
fwht(&mut b);
let inv = M::from(a.len()).inv();
a.dot_assign(&b);
fwht(&mut a);
for a in a.iter_mut() {
*a *= inv;
}
a
}
fn fwht(a: &mut [M]) {
bitwise_transform(a, |a, b| {
let x = *a + *b;
let y = *a - *b;
*a = x;
*b = y;
});
}
/*
順序付き、とりあえずソートしてみる?
値は小さめ、なんかできる?
最上位bitから分布を考える
40, 04 再帰
22, それぞれ畳み込み
13, 31, 片方が大きいことは確定
3個使って作れる値の分布がわかればok
22, 11 11 と分かれる場合が難しい
L, R
L^2R^2 - (L固定した時) - (R固定した時) + (L, R固定、0)
数列A, Bがある
sum_{i, j, k} |(A_i ^ B_k) - (A_j ^ B_k)|
ってどう計算する?
i,jの上位が等しいうちはB半分にしていく
相異なるようになった時
大小は決まるから分布計算
1,3 も壊れてた
L*R - R^2
*/
// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[macro_export]
macro_rules! input {
(source = $s:expr, $($r:tt)*) => {
let mut iter = $s.split_whitespace();
input_inner!{iter, $($r)*}
};
($($r:tt)*) => {
let s = {
use std::io::Read;
let mut s = String::new();
std::io::stdin().read_to_string(&mut s).unwrap();
s
};
let mut iter = s.split_whitespace();
input_inner!{iter, $($r)*}
};
}
#[macro_export]
macro_rules! input_inner {
($iter:expr) => {};
($iter:expr, ) => {};
($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
let $var = read_value!($iter, $t);
input_inner!{$iter $($r)*}
};
}
#[macro_export]
macro_rules! read_value {
($iter:expr, ( $($t:tt),* )) => {
( $(read_value!($iter, $t)),* )
};
($iter:expr, [ $t:tt ; $len:expr ]) => {
(0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
};
($iter:expr, chars) => {
read_value!($iter, String).chars().collect::<Vec<char>>()
};
($iter:expr, bytes) => {
read_value!($iter, String).bytes().collect::<Vec<u8>>()
};
($iter:expr, usize1) => {
read_value!($iter, usize) - 1
};
($iter:expr, $t:ty) => {
$iter.next().unwrap().parse::<$t>().expect("Parse error")
};
}
// ---------- end input macro ----------
// ---------- begin modint ----------
pub const fn pow_mod(mut r: u32, mut n: u32, m: u32) -> u32 {
let mut t = 1;
while n > 0 {
if n & 1 == 1 {
t = (t as u64 * r as u64 % m as u64) as u32;
}
r = (r as u64 * r as u64 % m as u64) as u32;
n >>= 1;
}
t
}
pub const fn primitive_root(p: u32) -> u32 {
let mut m = p - 1;
let mut f = [1; 30];
let mut k = 0;
let mut d = 2;
while d * d <= m {
if m % d == 0 {
f[k] = d;
k += 1;
}
while m % d == 0 {
m /= d;
}
d += 1;
}
if m > 1 {
f[k] = m;
k += 1;
}
let mut g = 1;
while g < p {
let mut ok = true;
let mut i = 0;
while i < k {
ok &= pow_mod(g, (p - 1) / f[i], p) > 1;
i += 1;
}
if ok {
break;
}
g += 1;
}
g
}
pub const fn is_prime(n: u32) -> bool {
if n <= 1 {
return false;
}
let mut d = 2;
while d * d <= n {
if n % d == 0 {
return false;
}
d += 1;
}
true
}
#[derive(Clone, Copy, PartialEq, Eq)]
pub struct ModInt<const M: u32>(u32);
impl<const M: u32> ModInt<{ M }> {
const REM: u32 = {
let mut t = 1u32;
let mut s = !M + 1;
let mut n = !0u32 >> 2;
while n > 0 {
if n & 1 == 1 {
t = t.wrapping_mul(s);
}
s = s.wrapping_mul(s);
n >>= 1;
}
t
};
const INI: u64 = ((1u128 << 64) % M as u128) as u64;
const IS_PRIME: () = assert!(is_prime(M));
const PRIMITIVE_ROOT: u32 = primitive_root(M);
const ORDER: usize = 1 << (M - 1).trailing_zeros();
const fn reduce(x: u64) -> u32 {
let _ = Self::IS_PRIME;
let b = (x as u32 * Self::REM) as u64;
let t = x + b * M as u64;
let mut c = (t >> 32) as u32;
if c >= M {
c -= M;
}
c as u32
}
const fn multiply(a: u32, b: u32) -> u32 {
Self::reduce(a as u64 * b as u64)
}
pub const fn new(v: u32) -> Self {
assert!(v < M);
Self(Self::reduce(v as u64 * Self::INI))
}
pub const fn const_mul(&self, rhs: Self) -> Self {
Self(Self::multiply(self.0, rhs.0))
}
pub const fn pow(&self, mut n: u64) -> Self {
let mut t = Self::new(1);
let mut r = *self;
while n > 0 {
if n & 1 == 1 {
t = t.const_mul(r);
}
r = r.const_mul(r);
n >>= 1;
}
t
}
pub const fn inv(&self) -> Self {
assert!(self.0 != 0);
self.pow(M as u64 - 2)
}
pub const fn get(&self) -> u32 {
Self::reduce(self.0 as u64)
}
pub const fn zero() -> Self {
Self::new(0)
}
pub const fn one() -> Self {
Self::new(1)
}
}
impl<const M: u32> Add for ModInt<{ M }> {
type Output = Self;
fn add(self, rhs: Self) -> Self::Output {
let mut v = self.0 + rhs.0;
if v >= M {
v -= M;
}
Self(v)
}
}
impl<const M: u32> Sub for ModInt<{ M }> {
type Output = Self;
fn sub(self, rhs: Self) -> Self::Output {
let mut v = self.0 - rhs.0;
if self.0 < rhs.0 {
v += M;
}
Self(v)
}
}
impl<const M: u32> Mul for ModInt<{ M }> {
type Output = Self;
fn mul(self, rhs: Self) -> Self::Output {
self.const_mul(rhs)
}
}
impl<const M: u32> Div for ModInt<{ M }> {
type Output = Self;
fn div(self, rhs: Self) -> Self::Output {
self * rhs.inv()
}
}
impl<const M: u32> AddAssign for ModInt<{ M }> {
fn add_assign(&mut self, rhs: Self) {
*self = *self + rhs;
}
}
impl<const M: u32> SubAssign for ModInt<{ M }> {
fn sub_assign(&mut self, rhs: Self) {
*self = *self - rhs;
}
}
impl<const M: u32> MulAssign for ModInt<{ M }> {
fn mul_assign(&mut self, rhs: Self) {
*self = *self * rhs;
}
}
impl<const M: u32> DivAssign for ModInt<{ M }> {
fn div_assign(&mut self, rhs: Self) {
*self = *self / rhs;
}
}
impl<const M: u32> Neg for ModInt<{ M }> {
type Output = Self;
fn neg(self) -> Self::Output {
if self.0 == 0 {
self
} else {
Self(M - self.0)
}
}
}
impl<const M: u32> std::fmt::Display for ModInt<{ M }> {
fn fmt<'a>(&self, f: &mut std::fmt::Formatter<'a>) -> std::fmt::Result {
write!(f, "{}", self.get())
}
}
impl<const M: u32> std::fmt::Debug for ModInt<{ M }> {
fn fmt<'a>(&self, f: &mut std::fmt::Formatter<'a>) -> std::fmt::Result {
write!(f, "{}", self.get())
}
}
impl<const M: u32> std::str::FromStr for ModInt<{ M }> {
type Err = std::num::ParseIntError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let val = s.parse::<u32>()?;
Ok(ModInt::new(val))
}
}
impl<const M: u32> From<usize> for ModInt<{ M }> {
fn from(val: usize) -> ModInt<{ M }> {
ModInt::new((val % M as usize) as u32)
}
}
// ---------- end modint ----------
// ---------- begin precalc ----------
pub struct Precalc<const MOD: u32> {
fact: Vec<ModInt<MOD>>,
ifact: Vec<ModInt<MOD>>,
inv: Vec<ModInt<MOD>>,
}
impl<const MOD: u32> Precalc<MOD> {
pub fn new(size: usize) -> Self {
let mut fact = vec![ModInt::one(); size + 1];
let mut ifact = vec![ModInt::one(); size + 1];
let mut inv = vec![ModInt::one(); size + 1];
for i in 2..=size {
fact[i] = fact[i - 1] * ModInt::from(i);
}
ifact[size] = fact[size].inv();
for i in (2..=size).rev() {
inv[i] = ifact[i] * fact[i - 1];
ifact[i - 1] = ifact[i] * ModInt::from(i);
}
Self { fact, ifact, inv }
}
pub fn fact(&self, n: usize) -> ModInt<MOD> {
self.fact[n]
}
pub fn ifact(&self, n: usize) -> ModInt<MOD> {
self.ifact[n]
}
pub fn inv(&self, n: usize) -> ModInt<MOD> {
assert!(0 < n);
self.inv[n]
}
pub fn perm(&self, n: usize, k: usize) -> ModInt<MOD> {
if k > n {
return ModInt::zero();
}
self.fact[n] * self.ifact[n - k]
}
pub fn binom(&self, n: usize, k: usize) -> ModInt<MOD> {
if n < k {
return ModInt::zero();
}
self.fact[n] * self.ifact[k] * self.ifact[n - k]
}
}
// ---------- end precalc ----------
impl<const M: u32> Zero for ModInt<{ M }> {
fn zero() -> Self {
Self::zero()
}
fn is_zero(&self) -> bool {
self.0 == 0
}
}
impl<const M: u32> One for ModInt<{ M }> {
fn one() -> Self {
Self::one()
}
fn is_one(&self) -> bool {
self.get() == 1
}
}
// ---------- begin array op ----------
struct NTTPrecalc<const M: u32> {
sum_e: [ModInt<{ M }>; 30],
sum_ie: [ModInt<{ M }>; 30],
}
impl<const M: u32> NTTPrecalc<{ M }> {
const fn new() -> Self {
let cnt2 = (M - 1).trailing_zeros() as usize;
let root = ModInt::new(ModInt::<{ M }>::PRIMITIVE_ROOT);
let zeta = root.pow((M - 1) as u64 >> cnt2);
let mut es = [ModInt::zero(); 30];
let mut ies = [ModInt::zero(); 30];
let mut sum_e = [ModInt::zero(); 30];
let mut sum_ie = [ModInt::zero(); 30];
let mut e = zeta;
let mut ie = e.inv();
let mut i = cnt2;
while i >= 2 {
es[i - 2] = e;
ies[i - 2] = ie;
e = e.const_mul(e);
ie = ie.const_mul(ie);
i -= 1;
}
let mut now = ModInt::one();
let mut inow = ModInt::one();
let mut i = 0;
while i < cnt2 - 1 {
sum_e[i] = es[i].const_mul(now);
sum_ie[i] = ies[i].const_mul(inow);
now = ies[i].const_mul(now);
inow = es[i].const_mul(inow);
i += 1;
}
Self { sum_e, sum_ie }
}
}
struct NTTPrecalcHelper<const MOD: u32>;
impl<const MOD: u32> NTTPrecalcHelper<MOD> {
const A: NTTPrecalc<MOD> = NTTPrecalc::new();
}
pub trait ArrayAdd {
type Item;
fn add(&self, rhs: &[Self::Item]) -> Vec<Self::Item>;
}
impl<T> ArrayAdd for [T]
where
T: Zero + Copy,
{
type Item = T;
fn add(&self, rhs: &[Self::Item]) -> Vec<Self::Item> {
let mut c = vec![T::zero(); self.len().max(rhs.len())];
c[..self.len()].copy_from_slice(self);
c.add_assign(rhs);
c
}
}
pub trait ArrayAddAssign {
type Item;
fn add_assign(&mut self, rhs: &[Self::Item]);
}
impl<T> ArrayAddAssign for [T]
where
T: Add<Output = T> + Copy,
{
type Item = T;
fn add_assign(&mut self, rhs: &[Self::Item]) {
assert!(self.len() >= rhs.len());
self.iter_mut().zip(rhs).for_each(|(x, a)| *x = *x + *a);
}
}
impl<T> ArrayAddAssign for Vec<T>
where
T: Zero + Add<Output = T> + Copy,
{
type Item = T;
fn add_assign(&mut self, rhs: &[Self::Item]) {
if self.len() < rhs.len() {
self.resize(rhs.len(), T::zero());
}
self.as_mut_slice().add_assign(rhs);
}
}
pub trait ArraySub {
type Item;
fn sub(&self, rhs: &[Self::Item]) -> Vec<Self::Item>;
}
impl<T> ArraySub for [T]
where
T: Zero + Sub<Output = T> + Copy,
{
type Item = T;
fn sub(&self, rhs: &[Self::Item]) -> Vec<Self::Item> {
let mut c = vec![T::zero(); self.len().max(rhs.len())];
c[..self.len()].copy_from_slice(self);
c.sub_assign(rhs);
c
}
}
pub trait ArraySubAssign {
type Item;
fn sub_assign(&mut self, rhs: &[Self::Item]);
}
impl<T> ArraySubAssign for [T]
where
T: Sub<Output = T> + Copy,
{
type Item = T;
fn sub_assign(&mut self, rhs: &[Self::Item]) {
assert!(self.len() >= rhs.len());
self.iter_mut().zip(rhs).for_each(|(x, a)| *x = *x - *a);
}
}
impl<T> ArraySubAssign for Vec<T>
where
T: Zero + Sub<Output = T> + Copy,
{
type Item = T;
fn sub_assign(&mut self, rhs: &[Self::Item]) {
if self.len() < rhs.len() {
self.resize(rhs.len(), T::zero());
}
self.as_mut_slice().sub_assign(rhs);
}
}
pub trait ArrayDot {
type Item;
fn dot(&self, rhs: &[Self::Item]) -> Vec<Self::Item>;
}
impl<T> ArrayDot for [T]
where
T: Mul<Output = T> + Copy,
{
type Item = T;
fn dot(&self, rhs: &[Self::Item]) -> Vec<Self::Item> {
assert!(self.len() == rhs.len());
self.iter().zip(rhs).map(|p| *p.0 * *p.1).collect()
}
}
pub trait ArrayDotAssign {
type Item;
fn dot_assign(&mut self, rhs: &[Self::Item]);
}
impl<T> ArrayDotAssign for [T]
where
T: MulAssign + Copy,
{
type Item = T;
fn dot_assign(&mut self, rhs: &[Self::Item]) {
assert!(self.len() == rhs.len());
self.iter_mut().zip(rhs).for_each(|(x, a)| *x *= *a);
}
}
pub trait ArrayMul {
type Item;
fn mul(&self, rhs: &[Self::Item]) -> Vec<Self::Item>;
}
impl<T> ArrayMul for [T]
where
T: Zero + One + Copy,
{
type Item = T;
fn mul(&self, rhs: &[Self::Item]) -> Vec<Self::Item> {
if self.is_empty() || rhs.is_empty() {
return vec![];
}
let mut res = vec![T::zero(); self.len() + rhs.len() - 1];
for (i, a) in self.iter().enumerate() {
for (res, b) in res[i..].iter_mut().zip(rhs.iter()) {
*res = *res + *a * *b;
}
}
res
}
}
// transform でlen=1を指定すればNTTになる
pub trait ArrayConvolution {
type Item;
fn transform(&mut self, len: usize);
fn inverse_transform(&mut self, len: usize);
fn convolution(&self, rhs: &[Self::Item]) -> Vec<Self::Item>;
}
impl<const M: u32> ArrayConvolution for [ModInt<{ M }>] {
type Item = ModInt<{ M }>;
fn transform(&mut self, len: usize) {
let f = self;
let n = f.len();
let k = (n / len).trailing_zeros() as usize;
assert!(len << k == n);
assert!(k <= ModInt::<{ M }>::ORDER);
let pre = &NTTPrecalcHelper::<{ M }>::A;
for ph in 1..=k {
let p = len << (k - ph);
let mut now = ModInt::one();
for (i, f) in f.chunks_exact_mut(2 * p).enumerate() {
let (x, y) = f.split_at_mut(p);
for (x, y) in x.iter_mut().zip(y.iter_mut()) {
let l = *x;
let r = *y * now;
*x = l + r;
*y = l - r;
}
now *= pre.sum_e[(!i).trailing_zeros() as usize];
}
}
}
fn inverse_transform(&mut self, len: usize) {
let f = self;
let n = f.len();
let k = (n / len).trailing_zeros() as usize;
assert!(len << k == n);
assert!(k <= ModInt::<{ M }>::ORDER);
let pre = &NTTPrecalcHelper::<{ M }>::A;
for ph in (1..=k).rev() {
let p = len << (k - ph);
let mut inow = ModInt::one();
for (i, f) in f.chunks_exact_mut(2 * p).enumerate() {
let (x, y) = f.split_at_mut(p);
for (x, y) in x.iter_mut().zip(y.iter_mut()) {
let l = *x;
let r = *y;
*x = l + r;
*y = (l - r) * inow;
}
inow *= pre.sum_ie[(!i).trailing_zeros() as usize];
}
}
let ik = ModInt::new(2).inv().pow(k as u64);
for f in f.iter_mut() {
*f *= ik;
}
}
fn convolution(&self, rhs: &[Self::Item]) -> Vec<Self::Item> {
if self.len().min(rhs.len()) <= 32 {
return self.mul(rhs);
}
const PARAM: usize = 10;
let size = self.len() + rhs.len() - 1;
let mut k = 0;
while (size + (1 << k) - 1) >> k > PARAM {
k += 1;
}
let len = (size + (1 << k) - 1) >> k;
let mut f = vec![ModInt::zero(); len << k];
let mut g = vec![ModInt::zero(); len << k];
f[..self.len()].copy_from_slice(self);
g[..rhs.len()].copy_from_slice(rhs);
f.transform(len);
g.transform(len);
let mut buf = [ModInt::zero(); 2 * PARAM - 1];
let buf = &mut buf[..(2 * len - 1)];
let pre = &NTTPrecalcHelper::<{ M }>::A;
let mut now = ModInt::one();
for (i, (f, g)) in f
.chunks_exact_mut(2 * len)
.zip(g.chunks_exact(2 * len))
.enumerate()
{
let mut r = now;
for (f, g) in f.chunks_exact_mut(len).zip(g.chunks_exact(len)) {
buf.fill(ModInt::zero());
for (i, f) in f.iter().enumerate() {
for (buf, g) in buf[i..].iter_mut().zip(g.iter()) {
*buf = *buf + *f * *g;
}
}
f.copy_from_slice(&buf[..len]);
for (f, buf) in f.iter_mut().zip(buf[len..].iter()) {
*f = *f + r * *buf;
}
r = -r;
}
now *= pre.sum_e[(!i).trailing_zeros() as usize];
}
f.inverse_transform(len);
f.truncate(self.len() + rhs.len() - 1);
f
}
}
// ---------- end array op ----------
// ---------- begin trait ----------
use std::ops::*;
pub trait Zero: Sized + Add<Self, Output = Self> {
fn zero() -> Self;
fn is_zero(&self) -> bool;
}
pub trait One: Sized + Mul<Self, Output = Self> {
fn one() -> Self;
fn is_one(&self) -> bool;
}
pub trait Group: Zero + Sub<Output = Self> + Neg<Output = Self> {}
pub trait SemiRing: Zero + One {}
pub trait Ring: SemiRing + Group {}
pub trait Field: Ring + Div<Output = Self> {}
impl<T> Group for T where T: Zero + Sub<Output = Self> + Neg<Output = Self> {}
impl<T> SemiRing for T where T: Zero + One {}
impl<T> Ring for T where T: SemiRing + Group {}
impl<T> Field for T where T: Ring + Div<Output = Self> {}
pub fn zero<T: Zero>() -> T {
T::zero()
}
pub fn one<T: One>() -> T {
T::one()
}
pub fn pow<T: One + Clone>(mut r: T, mut n: usize) -> T {
let mut t = one();
while n > 0 {
if n & 1 == 1 {
t = t * r.clone();
}
r = r.clone() * r;
n >>= 1;
}
t
}
pub fn pow_sum<T: SemiRing + Clone>(mut r: T, mut n: usize) -> T {
let mut ans = T::zero();
let mut sum = T::one();
while n > 0 {
if n & 1 == 1 {
ans = ans * r.clone() + sum.clone();
}
sum = sum * (T::one() + r.clone());
r = r.clone() * r;
n >>= 1;
}
ans
}
// ---------- end trait ----------
// ---------- begin bitwise transform ----------
pub fn bitwise_transform<T, F>(a: &mut [T], mut f: F)
where
F: FnMut(&mut T, &mut T),
{
let n = a.len().trailing_zeros() as usize;
assert!(a.len() == 1 << n);
for i in 0..n {
for a in a.chunks_exact_mut(2 << i) {
let (x, y) = a.split_at_mut(1 << i);
for (x, y) in x.iter_mut().zip(y) {
f(x, y);
}
}
}
}
// ---------- end bitwise transform ----------
fn rand_memory() -> usize {
Box::into_raw(Box::new("I hope this is a random number")) as usize
}
fn rand() -> usize {
static mut X: usize = 0;
unsafe {
if X == 0 {
X = rand_memory();
}
X ^= X << 13;
X ^= X >> 17;
X ^= X << 5;
X
}
}
fn shuffle<T>(a: &mut [T]) {
for i in 1..a.len() {
let p = rand() % (i + 1);
a.swap(i, p);
}
}
akakimidori