結果

問題 No.3429 Palindromic Path (Hard)
コンテスト
ユーザー Ohuton_Racing
提出日時 2026-01-11 14:31:58
言語 Rust
(1.92.0 + proconio + num)
結果
AC  
実行時間 1,289 ms / 2,000 ms
コード長 5,585 bytes
記録
記録タグの例:
初AC ショートコード 純ショートコード 純主流ショートコード 最速実行時間
コンパイル時間 24,248 ms
コンパイル使用メモリ 416,220 KB
実行使用メモリ 106,752 KB
最終ジャッジ日時 2026-01-11 14:32:29
合計ジャッジ時間 26,594 ms
ジャッジサーバーID
（参考情報） 		judge3 / judge4
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
sample AC * 3
other AC * 7
権限があれば一括ダウンロードができます
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)]` (part of `#[warn(unused)]`) 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 does not need to be mutable
   --> src/main.rs:151:9
    |
151 |     let mut vec: Vec<i64> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:156:9
    |
156 |     let mut vec: Vec<usize> = read_vec();
    |         ----^^^
    |         |
    |         help: remove this `mut`

warning: variable does not need to be mutable
   --> src/main.rs:178:13
    |
178 |         let mut pdp = dp[i - 1].clone();
    |             ----^^^
    |             |
    |             help: remove this `mut`

ソースコード

diff #
raw source code 

// -*- 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 = MOD9;
// 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])
}
#[allow(dead_code)]
fn readiiii() -> (i64, i64, i64, i64) {
    let mut vec: Vec<i64> = read_vec();
    (vec[0], vec[1], vec[2], vec[3])
}

fn readuuuu() -> (usize, usize, usize, usize) {
    let mut vec: Vec<usize> = read_vec();
    (vec[0], vec[1], vec[2], vec[3])
}

fn main() {
    let n: usize = read();
    let mut vv: Vec<Vec<char>> = vec![vec!['0' as char; (0) as usize]; (n) as usize];
    for i in 0..n {
        let s: String = read();
        let vvv = s.chars().collect();
        vv[i] = vvv;
    }
    let mut dp = vec![];
    if vv[0][0] == vv[n - 1][n - 1] {
        let mut bt = BTreeMap::new();
        bt.insert((0, 0, n - 1, n - 1), 1);
        dp.push(bt);
    } else {
        p!(0);
        return;
    }
    for i in 1..n {
        let mut pdp = dp[i - 1].clone();

        let mut ndp = BTreeMap::new();
        for (&key, &val) in pdp.iter() {
            let (x1, y1, x2, y2) = key;

            // d!(format!("{} {} {} {} {}",x1,y1,x2,y2,c));
            if x1 + 1 < n && x2 >= 1 && vv[x1 + 1][y1] == vv[x2 - 1][y2] {
                *ndp.entry((x1 + 1, y1, x2 - 1, y2)).or_insert(0) += val;
                *ndp.entry((x1 + 1, y1, x2 - 1, y2)).or_insert(0) %= MOD;
            }

            if y1 + 1 < n && x2 >= 1 && vv[x1][y1 + 1] == vv[x2 - 1][y2] {
                *ndp.entry((x1, y1 + 1, x2 - 1, y2)).or_insert(0) += val;
                *ndp.entry((x1, y1 + 1, x2 - 1, y2)).or_insert(0) %= MOD;
            }
            if x1 + 1 < n && y2 >= 1 && vv[x1 + 1][y1] == vv[x2][y2 - 1] {
                *ndp.entry((x1 + 1, y1, x2, y2 - 1)).or_insert(0) += val;
                *ndp.entry((x1 + 1, y1, x2, y2 - 1)).or_insert(0) %= MOD;
            }
            if y1 + 1 < n && y2 >= 1 && vv[x1][y1 + 1] == vv[x2][y2 - 1] {
                *ndp.entry((x1, y1 + 1, x2, y2 - 1)).or_insert(0) += val;
                *ndp.entry((x1, y1 + 1, x2, y2 - 1)).or_insert(0) %= MOD;
            }
        }
        let mut ok_ndp = BTreeMap::new();
        for (&key, &val) in ndp.iter() {
            let (x1, y1, x2, y2) = key;
            let dist = (x2 as i64 - x1 as i64).abs() + (y2 as i64 - y1 as i64).abs();
            if dist <= 2 * (n as i64 - 1 - i as i64) {
                ok_ndp.insert(key, val);
            }
        }

        dp.push(ok_ndp);
    }
    let mut ans = 0;
    for (&key, &val) in dp[n - 1].iter() {
        let (x1, y1, x2, y2) = key;
        if x1 == x2 && y1 == y2 {
            ans += val;
            ans %= MOD;
        }
    }
    p!(ans);

    return;
}
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