結果

問題 No.2914 正閉路検出
ユーザー atcoder8
提出日時 2024-10-05 06:19:22
言語 Rust
(1.83.0 + proconio)
結果
WA  
実行時間 -
コード長 3,734 bytes
コンパイル時間 13,095 ms
コンパイル使用メモリ 398,876 KB
実行使用メモリ 45,912 KB
最終ジャッジ日時 2024-10-05 06:19:41
合計ジャッジ時間 18,813 ms
ジャッジサーバーID
(参考情報)
judge4 / 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
other AC * 49 WA * 6
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

use proconio::{input, marker::Usize1};
fn main() {
match solve() {
Some(closed_path) => {
println!(
"{}\n{}\n{}",
closed_path.edges.len(),
closed_path.start + 1,
closed_path
.edges
.iter()
.map(|edge_id| (edge_id + 1).to_string())
.collect::<Vec<_>>()
.join(" ")
);
}
None => println!("-1"),
}
}
fn solve() -> Option<ClonedPath> {
input! {
(n, m): (usize, usize),
uvw: [(Usize1, Usize1, i64); m],
}
let mut graph = vec![vec![]; n];
for (id, &(u, v, w)) in uvw.iter().enumerate() {
let edge = Edge::new(id, u, v, w);
graph[u].push(edge);
graph[v].push(edge.inverse());
}
let create_increasing_closed_path =
|path: &[usize], nodes: &[Option<Node>], start: usize, potential: i64| {
let mut prev_path = vec![];
let mut current = start;
while current != 0 {
let passed_edge = nodes[current].unwrap().passed_edge.unwrap();
prev_path.push(passed_edge.id);
current = passed_edge.from;
}
prev_path.reverse();
let common_length = prev_path
.iter()
.zip(path)
.take_while(|(node1, node2)| node1 == node2)
.count();
let mut closed_path = prev_path[common_length..]
.iter()
.rev()
.chain(&path[common_length..])
.cloned()
.collect::<Vec<_>>();
if potential < nodes[start].unwrap().potential {
closed_path.reverse();
}
closed_path
};
let mut nodes: Vec<Option<Node>> = vec![None; n];
let mut stack: Vec<(Option<Edge>, i64, bool)> = vec![(None, 0, true)];
let mut path: Vec<usize> = vec![];
while let Some((passed_edge, potential, advance)) = stack.pop() {
if !advance {
path.pop().unwrap();
continue;
}
if let Some(edge) = passed_edge {
path.push(edge.id);
}
let current = passed_edge.map(|edge| edge.to).unwrap_or(0);
if let Some(node) = nodes[current] {
if potential != node.potential {
let closed_path = create_increasing_closed_path(&path, &nodes, current, potential);
return Some(ClonedPath {
start: current,
edges: closed_path,
});
}
continue;
}
nodes[current] = Some(Node {
potential,
passed_edge,
});
stack.extend(graph[current].iter().flat_map(|&next_edge| {
[
(passed_edge, potential, false),
(Some(next_edge), potential + next_edge.weight, true),
]
}));
}
None
}
#[allow(dead_code)]
#[derive(Debug, Clone, Copy)]
struct Edge {
id: usize,
from: usize,
to: usize,
weight: i64,
}
impl Edge {
fn new(id: usize, from: usize, to: usize, weight: i64) -> Self {
Self {
id,
from,
to,
weight,
}
}
fn inverse(&self) -> Self {
Self {
id: self.id,
from: self.to,
to: self.from,
weight: -self.weight,
}
}
}
#[derive(Debug, Clone, Copy)]
struct Node {
potential: i64,
passed_edge: Option<Edge>,
}
#[derive(Debug, Clone)]
struct ClonedPath {
start: usize,
edges: Vec<usize>,
}
הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
0