#423940 (Rust) No.977 アリス仕掛けの摩天楼

• 問題: No.977 アリス仕掛けの摩天楼
• ユーザー: akiradeveloper
• 提出日時: 2020-01-31 22:15:21
• 言語: Rust (1.77.0 + proconio)
• 結果: AC
• 実行時間: 42 ms / 2,000 ms
• コード長: 6,918 bytes
• コンパイル時間: 13,394 ms
• コンパイル使用メモリ: 402,544 KB
• 実行使用メモリ: 12,416 KB
• 最終ジャッジ日時: 2024-09-17 08:35:30
• 合計ジャッジ時間: 14,901 ms
• ジャッジサーバーID （参考情報）: judge4 / judge2

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 5,248 KB
testcase_01	AC	1 ms; 5,376 KB
testcase_02	AC	1 ms; 5,376 KB
testcase_03	AC	1 ms; 5,376 KB
testcase_04	AC	1 ms; 5,376 KB
testcase_05	AC	1 ms; 5,376 KB
testcase_06	AC	1 ms; 5,376 KB
testcase_07	AC	1 ms; 5,376 KB
testcase_08	AC	1 ms; 5,376 KB
testcase_09	AC	1 ms; 5,376 KB
testcase_10	AC	1 ms; 5,376 KB
testcase_11	AC	1 ms; 5,376 KB
testcase_12	AC	1 ms; 5,376 KB
testcase_13	AC	4 ms; 5,376 KB
testcase_14	AC	4 ms; 5,376 KB
testcase_15	AC	4 ms; 5,376 KB
testcase_16	AC	4 ms; 5,376 KB
testcase_17	AC	5 ms; 5,376 KB
testcase_18	AC	11 ms; 5,376 KB
testcase_19	AC	10 ms; 5,376 KB
testcase_20	AC	17 ms; 6,948 KB
testcase_21	AC	29 ms; 9,600 KB
testcase_22	AC	41 ms; 11,904 KB
testcase_23	AC	41 ms; 12,288 KB
testcase_24	AC	37 ms; 12,288 KB
testcase_25	AC	42 ms; 12,416 KB

コンパイルメッセージ

warning: unused variable: `out`
   --> src/main.rs:111:13
    |
111 |     let mut out = BufWriter::new(out.lock());
    |             ^^^ help: if this is intentional, prefix it with an underscore: `_out`
    |
    = note: `#[warn(unused_variables)]` on by default

warning: variable `cut0` is assigned to, but never used
   --> src/main.rs:128:13
    |
128 |     let mut cut0 = 0;
    |             ^^^^
    |
    = note: consider using `_cut0` instead

warning: variable does not need to be mutable
   --> src/main.rs:111:9
    |
111 |     let mut out = BufWriter::new(out.lock());
    |         ----^^^
    |         |
    |         help: remove this `mut`
    |
    = note: `#[warn(unused_mut)]` on by default

ソースコード

#[doc = " https://github.com/hatoo/competitive-rust-snippets"]
#[allow(unused_imports)]
use std::cmp::{max, min, Ordering};
#[allow(unused_imports)]
use std::collections::{BTreeMap, BTreeSet, BinaryHeap, HashMap, HashSet, VecDeque};
#[allow(unused_imports)]
use std::iter::FromIterator;
#[macro_export]
macro_rules ! chmax { ( $ x : expr , $ ( $ v : expr ) ,+ ) => { $ ( $ x = std :: cmp :: max ( $ x ,$ v ) ; ) + } ; }
#[macro_export]
macro_rules ! chmin { ( $ x : expr , $ ( $ v : expr ) ,+ ) => { $ ( $ x = std :: cmp :: min ( $ x ,$ v ) ; ) + } ; }
#[macro_export]
macro_rules ! max { ( $ x : expr ) => ( $ x ) ; ( $ x : expr , $ ( $ xs : expr ) ,+ ) => { std :: cmp :: max ( $ x , max ! ( $ ( $ xs ) ,+ ) ) } ; }
#[macro_export]
macro_rules ! min { ( $ x : expr ) => ( $ x ) ; ( $ x : expr , $ ( $ xs : expr ) ,+ ) => { std :: cmp :: min ( $ x , min ! ( $ ( $ xs ) ,+ ) ) } ; }
#[macro_export]
macro_rules ! dvec { ( $ t : expr ; $ len : expr ) => { vec ! [ $ t ; $ len ] } ; ( $ t : expr ; $ len : expr , $ ( $ rest : expr ) ,* ) => { vec ! [ dvec ! ( $ t ; $ ( $ rest ) ,* ) ; $ len ] } ; }
#[doc = " main"]
#[allow(unused_imports)]
use std::io::{stdin, stdout, BufWriter, Write};
#[macro_export]
macro_rules ! input { ( source = $ s : expr , $ ( $ r : tt ) * ) => { let mut parser = Parser :: from_str ( $ s ) ; input_inner ! { parser , $ ( $ r ) * } } ; ( parser = $ parser : ident , $ ( $ r : tt ) * ) => { input_inner ! { $ parser , $ ( $ r ) * } } ; ( new_stdin_parser = $ parser : ident , $ ( $ r : tt ) * ) => { let stdin = std :: io :: stdin ( ) ; let reader = std :: io :: BufReader :: new ( stdin . lock ( ) ) ; let mut $ parser = Parser :: new ( reader ) ; input_inner ! { $ parser , $ ( $ r ) * } } ; ( $ ( $ r : tt ) * ) => { input ! { new_stdin_parser = parser , $ ( $ r ) * } } ; }
#[macro_export]
macro_rules ! input_inner { ( $ parser : ident ) => { } ; ( $ parser : ident , ) => { } ; ( $ parser : ident , $ var : ident : $ t : tt $ ( $ r : tt ) * ) => { let $ var = read_value ! ( $ parser , $ t ) ; input_inner ! { $ parser $ ( $ r ) * } } ; }
#[macro_export]
macro_rules ! read_value { ( $ parser : ident , ( $ ( $ t : tt ) ,* ) ) => { ( $ ( read_value ! ( $ parser , $ t ) ) ,* ) } ; ( $ parser : ident , [ $ t : tt ; $ len : expr ] ) => { ( 0 ..$ len ) . map ( | _ | read_value ! ( $ parser , $ t ) ) . collect ::< Vec < _ >> ( ) } ; ( $ parser : ident , chars ) => { read_value ! ( $ parser , String ) . chars ( ) . collect ::< Vec < char >> ( ) } ; ( $ parser : ident , usize1 ) => { read_value ! ( $ parser , usize ) - 1 } ; ( $ parser : ident , $ t : ty ) => { $ parser . next ::<$ t > ( ) . expect ( "Parse error" ) } ; }
use std::io;
use std::io::BufRead;
use std::str;
pub struct Parser<R> {
    reader: R,
    buf: Vec<u8>,
    pos: usize,
}
impl Parser<io::Empty> {
    pub fn from_str(s: &str) -> Parser<io::Empty> {
        Parser {
            reader: io::empty(),
            buf: s.as_bytes().to_vec(),
            pos: 0,
        }
    }
}
impl<R: BufRead> Parser<R> {
    pub fn new(reader: R) -> Parser<R> {
        Parser {
            reader: reader,
            buf: vec![],
            pos: 0,
        }
    }
    pub fn update_buf(&mut self) {
        self.buf.clear();
        self.pos = 0;
        loop {
            let (len, complete) = {
                let buf2 = self.reader.fill_buf().unwrap();
                self.buf.extend_from_slice(buf2);
                let len = buf2.len();
                if len == 0 {
                    break;
                }
                (len, buf2[len - 1] <= 0x20)
            };
            self.reader.consume(len);
            if complete {
                break;
            }
        }
    }
    pub fn next<T: str::FromStr>(&mut self) -> Result<T, T::Err> {
        loop {
            let mut begin = self.pos;
            while begin < self.buf.len() && (self.buf[begin] <= 0x20) {
                begin += 1;
            }
            let mut end = begin;
            while end < self.buf.len() && (self.buf[end] > 0x20) {
                end += 1;
            }
            if begin != self.buf.len() {
                self.pos = end;
                return str::from_utf8(&self.buf[begin..end]).unwrap().parse::<T>();
            } else {
                self.update_buf();
            }
        }
    }
}
#[allow(unused_macros)]
macro_rules ! debug { ( $ ( $ a : expr ) ,* ) => { eprintln ! ( concat ! ( $ ( stringify ! ( $ a ) , " = {:?}, " ) ,* ) , $ ( $ a ) ,* ) ; } }
#[doc = " https://github.com/hatoo/competitive-rust-snippets"]
const BIG_STACK_SIZE: bool = true;
#[allow(dead_code)]
fn main() {
    use std::thread;
    if BIG_STACK_SIZE {
        thread::Builder::new()
            .stack_size(32 * 1024 * 1024)
            .name("solve".into())
            .spawn(solve)
            .unwrap()
            .join()
            .unwrap();
    } else {
        solve();
    }
}
fn solve() {
    let out = stdout();
    let mut out = BufWriter::new(out.lock());
    input!{
        n:usize,
        uv:[(usize,usize);n-1],
    }
    let mut g = vec![vec![];n];
    let mut uf = UnionFind::new(n);
    for (u,v) in uv {
        g[u].push(v);
        g[v].push(u);

        uf.merge(u, v);
    }
    let mut grp = HashSet::new();
    for i in 0..n {
        grp.insert(uf.root(i));
    }
    let mut cut0 = 0;
    let mut cut1 = 0;
    for i in 0..n {
        // 孤立点
        if g[i].len() == 0 {
            cut0 += 1;
        }
        // 切られて孤立する可能性がある
        if g[i].len() == 1 {
            cut1 += 1;
        }
    }
    if grp.len() >= 3 {
        println!("Alice");
    } else if grp.len() == 2 {
        if cut1 > 0 {
            println!("Alice");
        } else {
            println!("Bob");
        } 
    } else {
        println!("Bob");
    }
}

pub struct UnionFind {
    par: Vec<usize>,
    rank: Vec<usize>,
}
impl UnionFind {
    pub fn new(n: usize) -> UnionFind {
        UnionFind {
            par: (0..n).collect::<Vec<usize>>(),
            rank: vec![1; n],
        }
    }
    pub fn size(&mut self, x: usize) -> usize {
        let y = self.root(x);
        self.rank[y]
    }
    pub fn same(&mut self, x: usize, y: usize) -> bool {
        self.root(x) == self.root(y)
    }
    pub fn root(&mut self, x: usize) -> usize {
        if self.par[x] == x {
            return x;
        } else {
            let y = self.par[x];
            let z = self.root(y);
            self.par[x] = z;
            return z;
        }
    }
    pub fn merge(&mut self, x: usize, y: usize) -> bool {
        let mut a = self.root(x);
        let mut b = self.root(y);
        if a == b {
            return false;
        }
        if self.rank[a] < self.rank[b] {
            std::mem::swap(&mut a, &mut b);
        }
        assert!(self.rank[a] >= self.rank[b]);
        self.rank[a] += self.rank[b];
        self.par[b] = a;
        return true;
    }
}