結果
問題 | No.1553 Lovely City |
ユーザー |
![]() |
提出日時 | 2021-06-18 23:08:34 |
言語 | Rust (1.83.0 + proconio) |
結果 |
AC
|
実行時間 | 172 ms / 2,000 ms |
コード長 | 5,060 bytes |
コンパイル時間 | 12,259 ms |
コンパイル使用メモリ | 378,708 KB |
実行使用メモリ | 32,316 KB |
最終ジャッジ日時 | 2024-06-22 21:20:58 |
合計ジャッジ時間 | 19,157 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge5 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 26 |
ソースコード
//---------- begin union_find ----------pub struct DSU {p: Vec<i32>,}impl DSU {pub fn new(n: usize) -> DSU {assert!(n < std::i32::MAX as usize);DSU { p: vec![-1; n] }}pub fn init(&mut self) {self.p.iter_mut().for_each(|p| *p = -1);}pub fn root(&self, mut x: usize) -> usize {assert!(x < self.p.len());while self.p[x] >= 0 {x = self.p[x] as usize;}x}pub fn same(&self, x: usize, y: usize) -> bool {assert!(x < self.p.len() && y < self.p.len());self.root(x) == self.root(y)}pub fn unite(&mut self, x: usize, y: usize) -> Option<(usize, usize)> {assert!(x < self.p.len() && y < self.p.len());let mut x = self.root(x);let mut y = self.root(y);if x == y {return None;}if self.p[x] > self.p[y] {std::mem::swap(&mut x, &mut y);}self.p[x] += self.p[y];self.p[y] = x as i32;Some((x, y))}pub fn parent(&self, x: usize) -> Option<usize> {assert!(x < self.p.len());let p = self.p[x];if p >= 0 {Some(p as usize)} else {None}}pub fn sum<F>(&self, mut x: usize, mut f: F) -> usizewhereF: FnMut(usize),{while let Some(p) = self.parent(x) {f(x);x = p;}x}pub fn size(&self, x: usize) -> usize {assert!(x < self.p.len());let r = self.root(x);(-self.p[r]) as usize}}//---------- end union_find ----------// ---------- begin input macro ----------// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8macro_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 ----------fn run() {input! {n: usize,m: usize,cond: [(usize1, usize1); m],}let mut dsu = DSU::new(n);let mut edge = vec![vec![]; n];for (a, b) in cond {if let Some((x, y)) = dsu.unite(a, b) {let mut p = std::mem::take(&mut edge[y]);edge[x].append(&mut p);}edge[dsu.root(a)].push((a, b));}let mut ans = vec![];for i in 0..n {if i != dsu.root(i) {continue;}let edge = std::mem::take(&mut edge[i]);let mut z = vec![];z.extend(edge.iter().map(|e| e.0));z.extend(edge.iter().map(|e| e.1));z.sort();z.dedup();let n = z.len();let mut g = vec![vec![]; n];let mut deg = vec![0; n];for &(a, b) in edge.iter() {let a = z.binary_search(&a).unwrap();let b = z.binary_search(&b).unwrap();deg[b] += 1;g[a].push(b);}let mut topo = vec![];for i in 0..n {if deg[i] == 0 {topo.push(i);}}for i in 0..n {if i >= topo.len() {break;}let v = topo[i];for &u in g[v].iter() {deg[u] -= 1;if deg[u] == 0 {topo.push(u);}}}if topo.len() == n {for e in topo.windows(2) {ans.push((z[e[0]], z[e[1]]));}} else {let f = z[0];z.push(f);for z in z.windows(2) {ans.push((z[0], z[1]));}}}use std::io::Write;let out = std::io::stdout();let mut out = std::io::BufWriter::new(out.lock());writeln!(out, "{}", ans.len()).ok();for a in ans {writeln!(out, "{} {}", a.0 + 1, a.1 + 1).ok();}}fn main() {run();}