#397255 (Rust) No.922 東北きりきざむたん

• 問題: No.922 東北きりきざむたん
• ユーザー: fukafukatani
• 提出日時: 2019-11-09 18:08:32
• 言語: Rust (1.83.0 + proconio)
• 結果: RE
• 実行時間: -
• コード長: 6,708 bytes
• コンパイル時間: 16,038 ms
• コンパイル使用メモリ: 382,280 KB
• 実行使用メモリ: 52,864 KB
• 最終ジャッジ日時: 2024-09-15 04:41:26
• 合計ジャッジ時間: 19,253 ms
• ジャッジサーバーID （参考情報）: judge6 / judge3

ファイルパターン	結果
sample	AC * 3 RE * 1
other	AC * 9 RE * 17

コンパイルメッセージ

warning: method `get_size` is never used
   --> src/main.rs:243:8
    |
220 | impl UnionFindTree {
    | ------------------ method in this implementation
...
243 |     fn get_size(&mut self, x: usize) -> usize {
    |        ^^^^^^^^
    |
    = note: `#[warn(dead_code)]` on by default

ソースコード

#![allow(unused_imports)]
#![allow(non_snake_case)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let v = read_vec::<usize>();
    let (n, m, q) = (v[0], v[1], v[2]);
    let mut edges = vec![vec![]; n];
    let mut uft = UnionFindTree::new(n);
    for _ in 0..m {
        let v = read_vec::<usize>();
        let (a, b) = (v[0] - 1, v[1] - 1);
        edges[a].push(b);
        edges[b].push(a);
        uft.unite(a, b);
    }
    let mut used = vec![0; n];
    let mut imos = vec![0; n];
    let mut same_pairs = HashMap::new();
    for _ in 0..q {
        let v = read_vec::<usize>();
        let (a, b) = (v[0] - 1, v[1] - 1);
        if uft.same(a, b) {
            same_pairs.entry(uft.find(a)).or_insert(vec![]).push((a, b));
        } else {
            used[a] += 1;
            used[b] += 1;
        }
    }

    let mut roots = HashSet::new();
    for i in 0..n {
        let root = uft.find(i);
        if edges[root].is_empty() {
            continue;
        }
        roots.insert(root);
    }
    let mut ans = 0;
    let mut lca = LCA::new(&edges);

    for &root in roots.iter() {
        if same_pairs.contains_key(&root) {
            lca.dfs(root, None, 0, &edges);
            for &(a, b) in same_pairs[&root].iter() {
                let ca = lca.lca(a, b);
                ans += (lca.depth[a] + lca.depth[b] - lca.depth[ca]) as i64;
            }
        }

        let mut sum_count = 0;
        dfs1(
            root,
            root,
            root,
            &edges,
            &used,
            0,
            &mut sum_count,
            &mut imos,
        );
        let mut min_cost = std::i64::MAX;
        dfs2(root, root, sum_count, &edges, &mut min_cost, &mut imos);
        ans += min_cost;
    }
    println!("{}", ans);
}

fn dfs1(
    cur: usize,
    parent: usize,
    root: usize,
    edges: &Vec<Vec<usize>>,
    used: &Vec<i64>,
    depth: i64,
    sum_count: &mut i64,
    imos: &mut Vec<i64>,
) -> i64 {
    *sum_count += used[cur];
    imos[root] += (depth * used[cur]) as i64;
    let mut k = used[cur];
    for &child in edges[cur].iter() {
        if child == parent {
            continue;
        }
        k += dfs1(child, cur, root, edges, used, depth + 1, sum_count, imos);
    }
    if cur != root {
        imos[cur] = -2 * k;
    }
    k
}

fn dfs2(
    cur: usize,
    parent: usize,
    sum_count: i64,
    edges: &Vec<Vec<usize>>,
    min_cost: &mut i64,
    imos: &mut Vec<i64>,
) {
    *min_cost = min(*min_cost, imos[cur]);
    for &child in edges[cur].iter() {
        if child == parent {
            continue;
        }
        imos[child] += sum_count + imos[cur];
        dfs2(child, cur, sum_count, edges, min_cost, imos);
    }
}

pub struct LCA {
    pub depth: Vec<usize>,
    pub parent: Vec<Vec<Option<usize>>>,
}

impl LCA {
    pub fn new(g: &[Vec<usize>]) -> LCA {
        let n = g.len();
        let l2 = (1..).find(|i| 1usize << i > n).unwrap();
        let depth = vec![0; n];
        let parent = vec![vec![None; l2 + 1]; n];
        LCA {
            depth: depth,
            parent: parent,
        }
    }

    pub fn dfs(&mut self, i: usize, p: Option<usize>, d: usize, g: &[Vec<usize>]) {
        self.parent[i][0] = p;
        self.depth[i] = d;

        for &t in &g[i] {
            if Some(t) != p {
                self.dfs(t, Some(i), d + 1, g);
            }
        }
    }

    pub fn with_root(root: usize, g: &[Vec<usize>]) -> LCA {
        let n = g.len();
        let l2 = (1..).find(|i| 1usize << i > n).unwrap();
        let depth = vec![0; n];
        let parent = vec![vec![None; l2 + 1]; n];

        let mut lca = LCA {
            depth: depth,
            parent: parent,
        };
        lca.dfs(root, None, 0, &g);

        for i in 1..l2 + 1 {
            for j in 0..n {
                if let Some(p) = lca.parent[j][i - 1] {
                    lca.parent[j][i] = lca.parent[p][i - 1];
                }
            }
        }

        lca
    }

    pub fn lca(&self, mut a: usize, mut b: usize) -> usize {
        use std::mem::swap;
        if self.depth[b] < self.depth[a] {
            swap(&mut a, &mut b);
        }

        while self.depth[a] != self.depth[b] {
            b = self.parent[b][(self.depth[b] - self.depth[a]).trailing_zeros() as usize].unwrap();
        }

        if a == b {
            return a;
        }

        for i in (0..self.parent[0].len()).rev() {
            if self.parent[a][i] != self.parent[b][i] {
                a = self.parent[a][i].unwrap();
                b = self.parent[b][i].unwrap();
            }
        }
        self.parent[a][0].unwrap()
    }
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}

#[derive(Debug, Clone)]
struct UnionFindTree {
    parent: Vec<isize>,
    size: Vec<usize>,
    height: Vec<u64>,
}

impl UnionFindTree {
    fn new(n: usize) -> UnionFindTree {
        UnionFindTree {
            parent: vec![-1; n],
            size: vec![1usize; n],
            height: vec![0u64; n],
        }
    }

    fn find(&mut self, index: usize) -> usize {
        if self.parent[index] == -1 {
            return index;
        }
        let idx = self.parent[index] as usize;
        let ret = self.find(idx);
        self.parent[index] = ret as isize;
        ret
    }

    fn same(&mut self, x: usize, y: usize) -> bool {
        self.find(x) == self.find(y)
    }

    fn get_size(&mut self, x: usize) -> usize {
        let idx = self.find(x);
        self.size[idx]
    }

    fn unite(&mut self, index0: usize, index1: usize) -> bool {
        let a = self.find(index0);
        let b = self.find(index1);
        if a == b {
            false
        } else {
            if self.height[a] > self.height[b] {
                self.parent[b] = a as isize;
                self.size[a] += self.size[b];
            } else if self.height[a] < self.height[b] {
                self.parent[a] = b as isize;
                self.size[b] += self.size[a];
            } else {
                self.parent[b] = a as isize;
                self.size[a] += self.size[b];
                self.height[a] += 1;
            }
            true
        }
    }
}