結果

問題 No.1392 Don't be together
ユーザー akakimidoriakakimidori
提出日時 2021-02-12 22:33:41
言語 Rust
(1.83.0 + proconio)
結果
AC  
実行時間 180 ms / 2,000 ms
コード長 9,941 bytes
コンパイル時間 24,493 ms
コンパイル使用メモリ 383,372 KB
実行使用メモリ 5,376 KB
最終ジャッジ日時 2024-07-19 23:16:04
合計ジャッジ時間 15,698 ms
ジャッジサーバーID
(参考情報)
judge1 / judge3
このコードへのチャレンジ
(要ログイン)
ファイルパターン 結果
sample AC * 3
other AC * 27
権限があれば一括ダウンロードができます

ソースコード

diff #
プレゼンテーションモードにする

// ---------- begin ModInt ----------
mod modint {
#[allow(dead_code)]
pub struct Mod;
impl ConstantModulo for Mod {
const MOD: u32 = 998_244_353;
}
#[allow(dead_code)]
pub struct StaticMod;
static mut STATIC_MOD: u32 = 0;
impl Modulo for StaticMod {
fn modulo() -> u32 {
unsafe { STATIC_MOD }
}
}
#[allow(dead_code)]
impl StaticMod {
pub fn set_modulo(p: u32) {
unsafe {
STATIC_MOD = p;
}
}
}
use std::marker::*;
use std::ops::*;
pub trait Modulo {
fn modulo() -> u32;
}
pub trait ConstantModulo {
const MOD: u32;
}
impl<T> Modulo for T
where
T: ConstantModulo,
{
fn modulo() -> u32 {
T::MOD
}
}
pub struct ModInt<T>(pub u32, PhantomData<T>);
impl<T> Clone for ModInt<T> {
fn clone(&self) -> Self {
ModInt::new_unchecked(self.0)
}
}
impl<T> Copy for ModInt<T> {}
impl<T: Modulo> Add for ModInt<T> {
type Output = ModInt<T>;
fn add(self, rhs: Self) -> Self::Output {
let mut d = self.0 + rhs.0;
if d >= T::modulo() {
d -= T::modulo();
}
ModInt::new_unchecked(d)
}
}
impl<T: Modulo> AddAssign for ModInt<T> {
fn add_assign(&mut self, rhs: Self) {
*self = *self + rhs;
}
}
impl<T: Modulo> Sub for ModInt<T> {
type Output = ModInt<T>;
fn sub(self, rhs: Self) -> Self::Output {
let mut d = T::modulo() + self.0 - rhs.0;
if d >= T::modulo() {
d -= T::modulo();
}
ModInt::new_unchecked(d)
}
}
impl<T: Modulo> SubAssign for ModInt<T> {
fn sub_assign(&mut self, rhs: Self) {
*self = *self - rhs;
}
}
impl<T: Modulo> Mul for ModInt<T> {
type Output = ModInt<T>;
fn mul(self, rhs: Self) -> Self::Output {
let v = self.0 as u64 * rhs.0 as u64 % T::modulo() as u64;
ModInt::new_unchecked(v as u32)
}
}
impl<T: Modulo> MulAssign for ModInt<T> {
fn mul_assign(&mut self, rhs: Self) {
*self = *self * rhs;
}
}
impl<T: Modulo> Neg for ModInt<T> {
type Output = ModInt<T>;
fn neg(self) -> Self::Output {
if self.0 == 0 {
Self::zero()
} else {
Self::new_unchecked(T::modulo() - self.0)
}
}
}
impl<T> std::fmt::Display for ModInt<T> {
fn fmt<'a>(&self, f: &mut std::fmt::Formatter<'a>) -> std::fmt::Result {
write!(f, "{}", self.0)
}
}
impl<T> std::fmt::Debug for ModInt<T> {
fn fmt<'a>(&self, f: &mut std::fmt::Formatter<'a>) -> std::fmt::Result {
write!(f, "{}", self.0)
}
}
impl<T: Modulo> std::str::FromStr for ModInt<T> {
type Err = std::num::ParseIntError;
fn from_str(s: &str) -> Result<Self, Self::Err> {
let val = s.parse::<u32>()?;
Ok(ModInt::new(val))
}
}
impl<T: Modulo> From<usize> for ModInt<T> {
fn from(val: usize) -> ModInt<T> {
ModInt::new_unchecked((val % T::modulo() as usize) as u32)
}
}
impl<T: Modulo> From<u64> for ModInt<T> {
fn from(val: u64) -> ModInt<T> {
ModInt::new_unchecked((val % T::modulo() as u64) as u32)
}
}
impl<T: Modulo> From<i64> for ModInt<T> {
fn from(val: i64) -> ModInt<T> {
let m = T::modulo() as i64;
ModInt::new((val % m + m) as u32)
}
}
#[allow(dead_code)]
impl<T> ModInt<T> {
pub fn new_unchecked(d: u32) -> Self {
ModInt(d, PhantomData)
}
pub fn zero() -> Self {
ModInt::new_unchecked(0)
}
pub fn one() -> Self {
ModInt::new_unchecked(1)
}
pub fn is_zero(&self) -> bool {
self.0 == 0
}
}
#[allow(dead_code)]
impl<T: Modulo> ModInt<T> {
pub fn new(d: u32) -> Self {
ModInt::new_unchecked(d % T::modulo())
}
pub fn pow(&self, mut n: u64) -> Self {
let mut t = Self::one();
let mut s = *self;
while n > 0 {
if n & 1 == 1 {
t *= s;
}
s *= s;
n >>= 1;
}
t
}
pub fn inv(&self) -> Self {
assert!(self.0 != 0);
self.pow(T::modulo() as u64 - 2)
}
}
}
// ---------- end ModInt ----------
// ---------- begin Precalc ----------
mod precalc {
use super::modint::*;
#[allow(dead_code)]
pub struct Precalc<T> {
inv: Vec<ModInt<T>>,
fact: Vec<ModInt<T>>,
ifact: Vec<ModInt<T>>,
}
#[allow(dead_code)]
impl<T: Modulo> Precalc<T> {
pub fn new(n: usize) -> Precalc<T> {
let mut inv = vec![ModInt::one(); n + 1];
let mut fact = vec![ModInt::one(); n + 1];
let mut ifact = vec![ModInt::one(); n + 1];
for i in 2..(n + 1) {
fact[i] = fact[i - 1] * ModInt::new_unchecked(i as u32);
}
ifact[n] = fact[n].inv();
if n > 0 {
inv[n] = ifact[n] * fact[n - 1];
}
for i in (1..n).rev() {
ifact[i] = ifact[i + 1] * ModInt::new_unchecked((i + 1) as u32);
inv[i] = ifact[i] * fact[i - 1];
}
Precalc {
inv: inv,
fact: fact,
ifact: ifact,
}
}
pub fn inv(&self, n: usize) -> ModInt<T> {
assert!(n > 0);
self.inv[n]
}
pub fn fact(&self, n: usize) -> ModInt<T> {
self.fact[n]
}
pub fn ifact(&self, n: usize) -> ModInt<T> {
self.ifact[n]
}
pub fn perm(&self, n: usize, k: usize) -> ModInt<T> {
if k > n {
return ModInt::zero();
}
self.fact[n] * self.ifact[n - k]
}
pub fn comb(&self, n: usize, k: usize) -> ModInt<T> {
if k > n {
return ModInt::zero();
}
self.fact[n] * self.ifact[k] * self.ifact[n - k]
}
}
}
// ---------- end Precalc ----------
// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
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_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_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 ----------
use modint::*;
type M = ModInt<Mod>;
fn run() {
input! {
n: usize,
m: usize,
p: [usize1; n],
}
let mut used = vec![false; n];
let mut memo = vec![];
for i in 0..n {
if used[i] {
continue;
}
let mut cnt = 0;
let mut pos = i;
while !used[pos] {
cnt += 1;
used[pos] = true;
pos = p[pos];
}
//dp[x][y]
// x:
// y: y使
let mut dp = vec![vec![M::zero()]; 2];
dp[1][0] = M::one();
for _ in 1..cnt {
let mut next = vec![vec![M::zero(); dp[0].len() + 1]; 2];
for (x, dp) in dp.iter().enumerate() {
for (y, &v) in dp.iter().enumerate() {
if v.is_zero() {
continue;
}
if x == 1 {
next[0][y] += M::from(y) * v;
next[0][y + 1] += v;
} else {
next[0][y] += M::from(y - 1) * v;
next[0][y + 1] += v;
next[1][y] += v;
}
}
}
dp = next;
}
memo.push(dp.remove(0));
}
let pc = precalc::Precalc::new(n);
let mut ans = M::zero();
let mut sign = M::one();
for i in (1..=m).rev() {
let mut way = M::one();
for memo in memo.iter() {
let mut val = M::zero();
for (j, memo) in memo.iter().enumerate() {
let c = j + 1;
if c <= i {
val += *memo * pc.fact(i) * pc.ifact(i - c);
}
}
way *= val;
}
ans += sign * way * pc.comb(m, i);
sign = -sign;
}
ans *= pc.ifact(m);
println!("{}", ans);
}
fn main() {
run();
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0