#961222 (Rust) No.2677 Minmax Independent Set

提出ソース

結果

問題	No.2677 Minmax Independent Set
ユーザー	koba-e964
提出日時	2024-03-16 09:06:12
言語	Rust (1.77.0)
結果	AC
実行時間	478 ms / 2,000 ms
コード長	5,684 bytes
コンパイル時間	2,527 ms
コンパイル使用メモリ	203,236 KB
実行使用メモリ	130,088 KB
最終ジャッジ日時	2024-03-16 09:06:38
合計ジャッジ時間	18,285 ms
ジャッジサーバーID （参考情報）	judge13 / judge11

このコードへのチャレンジ
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テストケース

テストケース表示

入力	結果	実行時間実行使用メモリ
testcase_00	AC	1 ms 6,676 KB
testcase_01	AC	1 ms 6,676 KB
testcase_02	AC	1 ms 6,676 KB
testcase_03	AC	1 ms 6,676 KB
testcase_04	AC	1 ms 6,676 KB
testcase_05	AC	388 ms 91,060 KB
testcase_06	AC	381 ms 93,180 KB
testcase_07	AC	375 ms 93,216 KB
testcase_08	AC	375 ms 93,108 KB
testcase_09	AC	387 ms 95,228 KB
testcase_10	AC	318 ms 93,272 KB
testcase_11	AC	320 ms 93,272 KB
testcase_12	AC	308 ms 130,088 KB
testcase_13	AC	368 ms 105,272 KB
testcase_14	AC	356 ms 106,632 KB
testcase_15	AC	377 ms 115,204 KB
testcase_16	AC	442 ms 88,536 KB
testcase_17	AC	448 ms 88,536 KB
testcase_18	AC	271 ms 57,176 KB
testcase_19	AC	328 ms 67,180 KB
testcase_20	AC	96 ms 24,960 KB
testcase_21	AC	365 ms 74,276 KB
testcase_22	AC	21 ms 8,320 KB
testcase_23	AC	2 ms 6,676 KB
testcase_24	AC	1 ms 6,676 KB
testcase_25	AC	1 ms 6,676 KB
testcase_26	AC	1 ms 6,676 KB
testcase_27	AC	1 ms 6,676 KB
testcase_28	AC	294 ms 94,096 KB
testcase_29	AC	382 ms 115,672 KB
testcase_30	AC	1 ms 6,676 KB
testcase_31	AC	1 ms 6,676 KB
testcase_32	AC	1 ms 6,676 KB
testcase_33	AC	1 ms 6,676 KB
testcase_34	AC	1 ms 6,676 KB
testcase_35	AC	1 ms 6,676 KB
testcase_36	AC	1 ms 6,676 KB
testcase_37	AC	2 ms 6,676 KB
testcase_38	AC	2 ms 6,676 KB
testcase_39	AC	2 ms 6,676 KB
testcase_40	AC	5 ms 6,676 KB
testcase_41	AC	9 ms 6,676 KB
testcase_42	AC	19 ms 7,168 KB
testcase_43	AC	39 ms 12,416 KB
testcase_44	AC	89 ms 22,912 KB
testcase_45	AC	201 ms 43,776 KB
testcase_46	AC	445 ms 85,664 KB
testcase_47	AC	478 ms 86,956 KB
testcase_48	AC	451 ms 86,956 KB
testcase_49	AC	457 ms 87,080 KB
testcase_50	AC	107 ms 36,864 KB
testcase_51	AC	8 ms 6,676 KB
testcase_52	AC	266 ms 78,388 KB
testcase_53	AC	237 ms 72,316 KB
testcase_54	AC	7 ms 6,676 KB
testcase_55	AC	387 ms 94,132 KB
testcase_56	AC	385 ms 94,148 KB
testcase_57	AC	381 ms 94,136 KB
testcase_58	AC	386 ms 94,128 KB
testcase_59	AC	380 ms 94,132 KB
testcase_60	AC	191 ms 87,516 KB
testcase_61	AC	238 ms 88,276 KB
testcase_62	AC	207 ms 95,224 KB
testcase_63	AC	244 ms 114,708 KB

権限があれば一括ダウンロードができます

コンパイルメッセージ

warning: field `acc` is never read
  --> Main.rs:45:5
   |
44 | struct MonoidalReroot<M: Monoid> {
   |        -------------- field in this struct
45 |     acc: Vec<Vec<M::E>>,
   |     ^^^
   |
   = note: `#[warn(dead_code)]` on by default

warning: 1 warning emitted

ソースコード

raw source code

// https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
macro_rules! input {
    ($($r:tt)*) => {
        let stdin = std::io::stdin();
        let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock()));
        let mut next = move || -> String{
            bytes.by_ref().map(|r|r.unwrap() as char)
                .skip_while(|c|c.is_whitespace())
                .take_while(|c|!c.is_whitespace())
                .collect()
        };
        input_inner!{next, $($r)*}
    };
}

macro_rules! input_inner {
    ($next:expr) => {};
    ($next:expr,) => {};
    ($next:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($next, $t);
        input_inner!{$next $($r)*}
    };
}

macro_rules! read_value {
    ($next:expr, ( $($t:tt),* )) => { ($(read_value!($next, $t)),*) };
    ($next:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
    };
    ($next:expr, usize1) => (read_value!($next, usize) - 1);
    ($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error"));
}

trait Monoid {
    type V;
    type E: Clone;
    fn add(a: &Self::E, b: &Self::E) -> Self::E;
    fn e() -> Self::E;
    fn put_edge(a: &Self::V, eidx: EIdx) -> Self::E;
    fn put_vertex(a: &Self::E, vidx: usize) -> Self::V;
}

// Ported from https://trap.jp/post/1702/
struct MonoidalReroot<M: Monoid> {
    acc: Vec<Vec<M::E>>,
    acc_rev: Vec<Vec<M::E>>,
}
type EIdx = usize;

impl<M: Monoid> MonoidalReroot<M> {
    pub fn new(g: &[Vec<(usize, EIdx)>]) -> Self {
        let n = g.len();
        let mut acc = vec![vec![]; n];
        let mut acc_rev = vec![vec![]; n];
        let mut ch = vec![vec![]; n];
        for i in 0..n {
            acc[i] = vec![M::e(); g[i].len() + 1];
            acc_rev[i] = vec![M::e(); g[i].len() + 1];
        }
        Self::dfs1(0, n, &g, &mut ch);
        for i in 0..n {
            let l = ch[i].len();
            ch[i].sort_unstable_by_key(|&(eidx, _)| eidx);
            for j in 0..l {
                let val = M::add(&acc[i][j], &ch[i][j].1);
                acc[i][j + 1] = val;
            }
            for j in (0..l).rev() {
                let val = M::add(&acc_rev[i][j + 1], &ch[i][j].1);
                acc_rev[i][j] = val;
            }
        }
        Self::dfs2(0, n, &g, &mut ch, &acc, &acc_rev, M::e());
        for i in 0..n {
            let l = ch[i].len();
            ch[i].sort_unstable_by_key(|&(eidx, _)| eidx);
            for j in 0..l {
                let val = M::add(&acc[i][j], &ch[i][j].1);
                acc[i][j + 1] = val;
            }
            for j in (0..l).rev() {
                let val = M::add(&acc_rev[i][j + 1], &ch[i][j].1);
                acc_rev[i][j] = val;
            }
        }
        MonoidalReroot {
            acc: acc,
            acc_rev: acc_rev,
        }
    }
    fn dfs1(
        v: usize, par: usize, g: &[Vec<(usize, EIdx)>],
        ch: &mut [Vec<(EIdx, M::E)>],
    ) -> M::V {
        let mut me = M::e();
        for i in 0..g[v].len() {
            let (w, eidx) = g[v][i];
            if w == par { continue; }
            let chval = Self::dfs1(w, v, g, ch);
            let chval = M::put_edge(&chval, eidx);
            ch[v].push((eidx, chval.clone()));
            me = M::add(&me, &chval);
        }
        M::put_vertex(&me, v)
    }
    fn dfs2(
        v: usize, par: usize, g: &[Vec<(usize, EIdx)>],
        ch: &mut [Vec<(EIdx, M::E)>],
        acc: &[Vec<M::E>],
        acc_rev: &[Vec<M::E>],
        passed: M::E,
    ) {
        let mut parenteidx = None;
        for i in 0..g[v].len() {
            let (w, eidx) = g[v][i];
            if w == par {
                parenteidx = Some(eidx);
                continue;
            }
            let j = ch[v].binary_search_by_key(&eidx, |&(eidx, _)| eidx).unwrap();
            let inherited = M::add(&acc[v][j], &acc_rev[v][j + 1]);
            let inherited = if par >= g.len() {
                inherited
            } else {
                M::add(&inherited, &passed)
            };
            let inherited = M::put_vertex(&inherited, v);
            let inherited = M::put_edge(&inherited, eidx);
            Self::dfs2(w, v, g, ch, acc, acc_rev, inherited);
        }
        if let Some(eidx) = parenteidx {
            ch[v].push((eidx, passed.clone()));
        }
    }
    #[inline]
    pub fn query(&self, v: usize) -> M::V {
        M::put_vertex(&self.acc_rev[v][0], v)
    }
}

enum IndepMonoid {}

impl Monoid for IndepMonoid {
    type V = [i64; 2]; // [その頂点を使わない, 使う]
    type E = [i64; 2]; // [一番上を使わない, 使っても良い]
    fn add(a: &Self::E, b: &Self::E) -> Self::E {
        [a[0] + b[0], a[1] + b[1]]
    }
    fn e() -> Self::E {
        [0, 0]
    }
    fn put_edge(&a: &Self::V, _eidx: EIdx) -> Self::E {
        [a[0], std::cmp::max(a[0], a[1])]
    }
    fn put_vertex(a: &Self::E, _vidx: usize) -> Self::V {
        [a[1], a[0] + 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();
}

// Tags: rerooting
fn solve() {
    input! {
        n: usize,
        uv: [(usize1, usize1); n - 1],
    }
    let mut g = vec![vec![]; n];
    for i in 0..n - 1 {
        let (u, v) = uv[i];
        g[u].push((v, i));
        g[v].push((u, i + n));
    }
    let rr = MonoidalReroot::<IndepMonoid>::new(&g);
    let mut ans = rr.query(0)[1];
    for i in 1..n {
        ans = std::cmp::min(ans, rr.query(i)[1]);
    }
    println!("{}", ans);
}

yukicoder

結果

テストケース

コンパイルメッセージ

ソースコード