#1105826 (Rust) No.3206 う し た ウ ニ 木 あ く ん 笑

• 問題: No.3206 う し た ウ ニ 木 あ く ん 笑
• ユーザー: Moss_Local
• 提出日時: 2025-07-18 23:19:43
• 言語: Rust (1.83.0 + proconio)
• 結果: RE
• 実行時間: -
• コード長: 5,959 bytes
• コンパイル時間: 12,839 ms
• コンパイル使用メモリ: 398,976 KB
• 実行使用メモリ: 33,364 KB
• 最終ジャッジ日時: 2025-07-18 23:20:00
• 合計ジャッジ時間: 16,029 ms
• ジャッジサーバーID （参考情報）: judge5 / judge4

ファイルパターン	結果
sample	RE * 2
other	RE * 30

コンパイルメッセージ

warning: variable does not need to be mutable
   --> src/main.rs:119:9
    |
119 |     let mut vec: Vec<i64> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`
    |
    = note: `#[warn(unused_mut)]` on by default

warning: variable does not need to be mutable
   --> src/main.rs:125:9
    |
125 |     let mut vec: Vec<i64> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:130:9
    |
130 |     let mut vec: Vec<usize> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:136:9
    |
136 |     let mut vec: Vec<f64> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:141:9
    |
141 |     let mut vec: Vec<char> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:146:9
    |
146 |     let mut vec: Vec<usize> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable `L` should have a snake case name
   --> src/main.rs:182:18
    |
182 |         for (i, &L) in d.iter().enumerate() {
    |                  ^ help: convert the identifier to snake case: `l`
    |
    = note: `#[warn(non_snake_case)]` on by default

ソースコード

// -*- coding:utf-8-unix -*-
// #![feature(map_first_last)]
#![allow(dead_code)]
#![allow(unused_imports)]
#![allow(unused_macros)]
// use core::num;
use std::cmp::*;
use std::fmt::*;
use std::hash::*;
use std::io::BufRead;
use std::iter::FromIterator;
use std::*;
use std::{cmp, collections, fmt, io, iter, ops, str};
const INF: i64 = 1223372036854775807;
const UINF: usize = INF as usize;
const LINF: i64 = 2147483647;
const INF128: i128 = 1223372036854775807000000000000;
const MOD1: i64 = 1000000007;
const MOD9: i64 = 998244353;
const MOD: i64 = MOD1;
// const MOD: i64 = MOD2;
const UMOD: usize = MOD as usize;
const M_PI: f64 = 3.14159265358979323846;

// use proconio::input;
// const MOD: i64 = INF;

use cmp::Ordering::*;
use std::collections::*;

use std::io::stdin;
use std::io::stdout;
use std::io::Write;

macro_rules! p {
    ($x:expr) => {
        //if expr
        println!("{}", $x);
    };
}

macro_rules! vp {
    // vector print separate with space
    ($x:expr) => {
        println!(
            "{}",
            $x.iter()
                .map(|x| x.to_string())
                .collect::<Vec<_>>()
                .join(" ")
        );
    };
}

macro_rules! d {
    ($x:expr) => {
        eprintln!("{:?}", $x);
    };
}
macro_rules! yn {
    ($val:expr) => {
        if $val {
            println!("Yes");
        } else {
            println!("No");
        }
    };
}

macro_rules! map{
    // declear btreemap
    ($($key:expr => $val:expr),*) => {
        {
            let mut map = ::std::collections::BTreeMap::new();
            $(
                map.insert($key, $val);
            )*
            map
        }
    };
}

macro_rules! set{
    // declear btreemap
    ($($key:expr),*) => {
        {
            let mut set = ::std::collections::BTreeSet::new();
            $(
                set.insert($key);
            )*
            set
        }
    };
}

//input output
#[allow(dead_code)]
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()
}

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

#[allow(dead_code)]
fn read_mat<T: std::str::FromStr>(n: u32) -> Vec<Vec<T>> {
    (0..n).map(|_| read_vec()).collect()
}

#[allow(dead_code)]
fn readii() -> (i64, i64) {
    let mut vec: Vec<i64> = read_vec();
    (vec[0], vec[1])
}

#[allow(dead_code)]
fn readiii() -> (i64, i64, i64) {
    let mut vec: Vec<i64> = read_vec();
    (vec[0], vec[1], vec[2])
}
#[allow(dead_code)]
fn readuu() -> (usize, usize) {
    let mut vec: Vec<usize> = read_vec();
    (vec[0], vec[1])
}

#[allow(dead_code)]
fn readff() -> (f64, f64) {
    let mut vec: Vec<f64> = read_vec();
    (vec[0], vec[1])
}

fn readcc() -> (char, char) {
    let mut vec: Vec<char> = read_vec();
    (vec[0], vec[1])
}

fn readuuu() -> (usize, usize, usize) {
    let mut vec: Vec<usize> = read_vec();
    (vec[0], vec[1], vec[2])
}

fn main() {
    let n: usize = read();
    let edges: Vec<(usize, usize)> = (0..n - 1)
        .map(|_| {
            let (u, v) = readuu();
            (u, v)
        })
        .collect();

    let dp_all: Vec<Vec<usize>> = rerooting_dp(
        &edges,
        Vec::new(),
        |a: &Vec<usize>, b: &Vec<usize>| {
            let mut c = a.clone();
            c.extend(b.iter());
            c
        },
        |_, _| Vec::from([0]),
        |a, _| {
            let mut v = a.clone();
            for x in &mut v {
                *x += 1;
            }
            v
        },
    );

    let mut ans: i64 = 1;
    for depths in dp_all {
        let mut d = depths;
        d.sort_unstable_by(|a, b| b.cmp(a));
        let mut best: i64 = 0;
        for (i, &L) in d.iter().enumerate() {
            let k = (i + 1) as i64;
            best = max(best, k * (L as i64));
        }
        ans = max(ans, best + 1);
    }
    println!("{}", ans);
}

// --- rerooting library ---

pub fn rerooting_dp<T, F, G, H>(edge: &[(usize, usize)], id: T, f: F, g: G, h: H) -> Vec<T>
where
    T: Clone + Default + std::fmt::Debug,
    F: Fn(&T, &T) -> T,
    G: Fn(&T, usize) -> T,
    H: Fn(&T, usize) -> T,
{
    let n = edge.len() + 1;
    let mut adj = vec![vec![]; n];
    let mut ix_for_adj = vec![vec![]; n];
    for &(i, j) in edge {
        ix_for_adj[i].push(adj[j].len());
        ix_for_adj[j].push(adj[i].len());
        adj[i].push(j);
        adj[j].push(i);
    }
    let mut order = Vec::with_capacity(n);
    let mut parent = vec![0; n];
    let mut ix_for_parent = vec![0; n];
    let mut stack = vec![0];
    while let Some(i) = stack.pop() {
        order.push(i);
        for (ix, &j) in adj[i].iter().enumerate() {
            if j != parent[i] {
                stack.push(j);
                parent[j] = i;
                ix_for_parent[j] = ix;
            }
        }
    }
    let mut dp: Vec<_> = adj.iter().map(|a| vec![T::default(); a.len()]).collect();
    for &i in order.iter().rev().skip(1) {
        let mut prod = id.clone();
        for (ix, &j) in adj[i].iter().enumerate().filter(|&(_, &j)| j != parent[i]) {
            prod = f(&prod, &g(&dp[i][ix], j));
        }
        dp[parent[i]][ix_for_parent[i]] = h(&prod, parent[i]);
    }
    let mut ret = vec![T::default(); n];
    for &i in &order {
        let m = adj[i].len();
        let mut accum_back = vec![T::default(); m];
        *accum_back.last_mut().unwrap() = id.clone();
        for j in (1..m).rev() {
            accum_back[j - 1] = f(&g(&dp[i][j], adj[i][j]), &accum_back[j]);
        }
        let mut accum = id.clone();
        for (ix, &j) in adj[i].iter().enumerate() {
            let prod = f(&accum, &accum_back[ix]);
            dp[j][ix_for_adj[i][ix]] = h(&prod, j);
            accum = f(&accum, &g(&dp[i][ix], j));
        }
        ret[i] = h(&accum, i);
    }
    ret
}