#462901 (Rust) No.1023 Cyclic Tour

• 問題: No.1023 Cyclic Tour
• ユーザー: cotton_fn_
• 提出日時: 2020-04-11 23:12:02
• 言語: Rust (1.83.0 + proconio)
• 結果: AC
• 実行時間: 156 ms / 2,000 ms
• コード長: 6,808 bytes
• コンパイル時間: 13,862 ms
• コンパイル使用メモリ: 399,284 KB
• 実行使用メモリ: 39,604 KB
• 最終ジャッジ日時: 2024-09-19 16:09:25
• 合計ジャッジ時間: 20,834 ms
• ジャッジサーバーID （参考情報）: judge3 / judge2

ファイルパターン	結果
sample	AC * 4
other	AC * 49

ソースコード

#![allow(unused)]

use kyoproio::*;
use std::{
    collections::*,
    io::{self, prelude::*},
    iter,
    mem::{replace, swap},
};

fn main() -> io::Result<()> {
    std::thread::Builder::new()
        .stack_size(10 * 1024 * 1024)
        .spawn(solve)?
        .join()
        .unwrap();
    Ok(())
}

fn solve() {
    let stdin = io::stdin();
    let mut kin = KInput::new(stdin.lock());
    let stdout = io::stdout();
    let mut out = io::BufWriter::new(stdout.lock());
    macro_rules! output {
        ($($args:expr),+) => { write!(&mut out, $($args),+) };
    }
    macro_rules! outputln {
        ($($args:expr),+) => { output!($($args),+); outputln!(); };
        () => { output!("\n"); if cfg!(debug_assertions) { out.flush(); } }
    }

    let (n, m): (usize, usize) = kin.input();
    let mut uf = UnionFind::new(n + 1);
    let mut g = vec![vec![]; n + 1];
    let mut cy = false;
    for (a, b, c) in kin.iter::<(usize, usize, char)>().take(m) {
        match c {
            '1' => if !uf.unite(a, b) {
                cy = true;
            }
            '2' => g[a].push(b),
            _ => {}
        }
    }
    if cy {
        outputln!("Yes");
        return;
    }
    let mut h = vec![vec![]; n + 1];
    for u in 1..=n {
        for &v in &g[u] {
            let ru = uf.root(u);
            let rv = uf.root(v);
            if ru == rv {
                outputln!("Yes");
                return;
            }
            h[ru].push(rv);
        }
    }
    let scc = strongly_connected_components(&h);
    for c in scc {
        if c.len() >= 2 {
            outputln!("Yes");
            return;
        }
    }
    outputln!("No");
}
pub struct UnionFind {
    p: Vec<isize>,
}
impl UnionFind {
    pub fn new(n: usize) -> Self {
        Self { p: vec![-1; n] }
    }
    pub fn root(&self, mut u: usize) -> usize {
        while self.p[u] >= 0 {
            u = self.p[u] as usize;
        }
        u
    }
    pub fn size(&self, u: usize) -> usize {
        (-self.p[self.root(u)]) as usize
    }
    pub fn unite(&mut self, u: usize, v: usize) -> bool {
        let mut u = self.root(u);
        let mut v = self.root(v);
        if u == v {
            return false;
        }
        if self.p[u] > self.p[v] {
            swap(&mut u, &mut v);
        }
        self.p[u] += self.p[v];
        self.p[v] = u as isize;
        true
    }
    pub fn is_same(&self, u: usize, v: usize) -> bool {
        self.root(u) == self.root(v)
    }
}

fn strongly_connected_components(g: &[Vec<usize>]) -> Vec<Vec<usize>> {
    let mut ord = Vec::with_capacity(g.len());
    let mut vis = vec![false; g.len()];
    for u in 0..g.len() {
        if !vis[u] {
            dfs_f(g, u, &mut ord, &mut vis);
        }
    }
    let mut comps = Vec::new();
    let mut h = vec![Vec::new(); g.len()];
    for u in 0..g.len() {
        for &v in &g[u] {
            h[v].push(u);
        }
    }
    vis.iter_mut().for_each(|v| *v = false);
    for u in ord.into_iter().rev() {
        if !vis[u] {
            let mut comp = Vec::new();
            dfs_c(&h, u, &mut comp, &mut vis);
            comps.push(comp);
        }
    }
    comps
}
fn dfs_f(g: &[Vec<usize>], u: usize, ord: &mut Vec<usize>, vis: &mut [bool]) {
    vis[u] = true;
    for &v in &g[u] {
        if !vis[v] {
            dfs_f(g, v, ord, vis);
        }
    }
    ord.push(u);
}
fn dfs_c(h: &[Vec<usize>], u: usize, comp: &mut Vec<usize>, vis: &mut [bool]) {
    vis[u] = true;
    comp.push(u);
    for &v in &h[u] {
        if !vis[v] {
            dfs_c(h, v, comp, vis);
        }
    }
}

// -----------------------------------------------------------------------------
pub mod kyoproio {
    #![warn(unused)]
    use std::io::prelude::*;
    pub trait Input {
        fn str(&mut self) -> &str;
        fn bytes(&mut self) -> &[u8] {
            self.str().as_ref()
        }
        fn input<T: InputParse>(&mut self) -> T {
            T::input(self).expect("input error")
        }
        fn iter<T: InputParse>(&mut self) -> Iter<T, Self> {
            Iter(self, std::marker::PhantomData)
        }
        fn seq<T: InputParse, B: std::iter::FromIterator<T>>(&mut self, n: usize) -> B {
            self.iter().take(n).collect()
        }
    }
    pub struct KInput<R> {
        src: R,
        buf: String,
        pos: usize,
    }
    impl<R: BufRead> KInput<R> {
        pub fn new(src: R) -> Self {
            Self {
                src,
                buf: String::with_capacity(1024),
                pos: 0,
            }
        }
    }
    impl<R: BufRead> Input for KInput<R> {
        fn str(&mut self) -> &str {
            loop {
                if self.pos >= self.buf.len() {
                    self.pos = 0;
                    self.buf.clear();
                    if self.src.read_line(&mut self.buf).expect("io error") == 0 {
                        return &self.buf;
                    }
                }
                let range = self.pos
                    ..self.buf[self.pos..]
                        .find(|c: char| c.is_ascii_whitespace())
                        .map(|i| i + self.pos)
                        .unwrap_or_else(|| self.buf.len());
                self.pos = range.end + 1;
                if range.end > range.start {
                    return &self.buf[range];
                }
            }
        }
    }
    pub struct Iter<'a, T, I: ?Sized>(&'a mut I, std::marker::PhantomData<*const T>);
    impl<'a, T: InputParse, I: Input + ?Sized> Iterator for Iter<'a, T, I> {
        type Item = T;
        fn next(&mut self) -> Option<Self::Item> {
            Some(self.0.input())
        }
    }
    pub trait InputParse: Sized {
        type Err: std::fmt::Debug;
        fn input<I: Input + ?Sized>(input: &mut I) -> Result<Self, Self::Err>;
    }
    macro_rules! from_str_impls {
        { $($T:ty)* } => {
            $(impl InputParse for $T {
                type Err = <$T as std::str::FromStr>::Err;
                fn input<I: Input + ?Sized>(input: &mut I) -> Result<Self, Self::Err> {
                    input.str().parse::<$T>()
                }
            })*
        };
    }
    from_str_impls! {
        String char bool f32 f64 isize i8 i16 i32 i64 i128 usize u8 u16 u32 u64 u128
    }
    macro_rules! tuple_impls {
        ($H:ident $($T:ident)*) => {
            impl<$H: InputParse, $($T: InputParse),*> InputParse for ($H, $($T),*) {
                type Err = std::convert::Infallible;
                fn input<I: Input + ?Sized>(input: &mut I) -> Result<Self, Self::Err> {
                    // ?
                    Ok(($H::input(input).unwrap(), $($T::input(input).unwrap()),*))
                }
            }
            tuple_impls!($($T)*);
        };
        () => {};
    }
    tuple_impls!(A B C D E F G);
}