#371632 (Rust) No.599 回文かい

• 問題: No.599 回文かい
• ユーザー: akiradeveloper
• 提出日時: 2019-08-22 12:12:02
• 言語: Rust (1.77.0)
• 結果: AC
• 実行時間: 825 ms / 4,000 ms
• コード長: 6,263 bytes
• コンパイル時間: 5,482 ms
• コンパイル使用メモリ: 160,340 KB
• 実行使用メモリ: 4,384 KB
• 最終ジャッジ日時: 2023-08-02 10:03:31
• 合計ジャッジ時間: 9,878 ms
• ジャッジサーバーID （参考情報）: judge14 / judge11

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 4,376 KB
testcase_01	AC	1 ms; 4,380 KB
testcase_02	AC	1 ms; 4,376 KB
testcase_03	AC	1 ms; 4,376 KB
testcase_04	AC	3 ms; 4,376 KB
testcase_05	AC	2 ms; 4,376 KB
testcase_06	AC	2 ms; 4,380 KB
testcase_07	AC	2 ms; 4,380 KB
testcase_08	AC	2 ms; 4,380 KB
testcase_09	AC	2 ms; 4,380 KB
testcase_10	AC	386 ms; 4,380 KB
testcase_11	AC	227 ms; 4,376 KB
testcase_12	AC	437 ms; 4,380 KB
testcase_13	AC	252 ms; 4,380 KB
testcase_14	AC	658 ms; 4,380 KB
testcase_15	AC	761 ms; 4,376 KB
testcase_16	AC	724 ms; 4,376 KB
testcase_17	AC	825 ms; 4,376 KB
testcase_18	AC	1 ms; 4,384 KB
testcase_19	AC	1 ms; 4,380 KB
testcase_20	AC	2 ms; 4,376 KB
evil_0.txt	AC	549 ms; 4,380 KB

コンパイルメッセージ

warning: unnecessary parentheses around `for` iterator expression
   --> Main.rs:122:18
    |
122 |         for j in (i+1..mid+1) {
    |                  ^          ^
    |
    = note: `#[warn(unused_parens)]` on by default
help: remove these parentheses
    |
122 -         for j in (i+1..mid+1) {
122 +         for j in i+1..mid+1 {
    |

warning: variable `S` should have a snake case name
   --> Main.rs:105:9
    |
105 |         S: chars,
    |         ^ help: convert the identifier to snake case (notice the capitalization): `s`
    |
    = note: `#[warn(non_snake_case)]` on by default

warning: 2 warnings emitted

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::io::{stdin, stdout, BufWriter, Write};
#[allow(unused_imports)]
use std::iter::FromIterator;
#[allow(unused_macros)]
macro_rules ! debug { ( $ ( $ a : expr ) ,* ) => { eprintln ! ( concat ! ( $ ( stringify ! ( $ a ) , " = {:?}, " ) ,* ) , $ ( $ a ) ,* ) ; } }
#[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 ctoi(x: char) -> u64 {
    x as u64 - 'a' as u64
}
fn solve() {
    input! {
        S: chars,
    }
    let p = 1_000_000_007;
    let s: Vec<u64> = S.iter().map(|&x| ctoi(x)).collect();
    let rh = RollingHash::new(&s);
    let gamma = |i: usize, j: usize| {
        let h1 = rh.get(i, j);
        let h2 = rh.get(s.len()-j, s.len()-i);
        if h1 == h2 {
            1
        } else { 0 }
    };
    let mid = s.len()/2;
    let mut dp = vec![0; mid+1];
    dp[s.len()/2] = 1;
    for i in (0..mid).rev() {
        let mut sum = 1; // for i,i
        for j in (i+1..mid+1) {
            // dbg!(sum,i,j,gamma(i,j));
            sum += gamma(i,j) * dp[j];
            sum %= p;
        }
        dp[i] = sum;
    }
    println!("{}", dp[0]);
}

#[allow(dead_code)]
/// Rolling hash algorithm
pub struct RollingHash {
    hash_pow_list: Vec<(u64, Vec<(u64, u64)>)>,
}

#[allow(dead_code)]
impl RollingHash {
    pub fn new(s: &[u64]) -> RollingHash {
        RollingHash::with_base_mod_pairs(s, &[(1009, 1_000_000_007), (9973, 999_999_937)])
    }

    pub fn with_base_mod_pairs(s: &[u64], base_mod_pairs: &[(u64, u64)]) -> RollingHash {
        let hp_list = base_mod_pairs
            .iter()
            .map(|&(base, m)| {
                let mut hp = Vec::with_capacity(s.len() + 1);
                hp.push((0, 1));

                for (i, &x) in s.iter().enumerate() {
                    let (h, p) = hp[i];
                    hp.push(((h + x) * base % m, p * base % m));
                }
                (m, hp)
            })
            .collect();

        RollingHash {
            hash_pow_list: hp_list,
        }
    }

    // [l, r)
    pub fn get(&self, l: usize, r: usize) -> u64 {
        self.hash_pow_list
            .iter()
            .map(|&(m, ref hp)| (hp[r].0 + m - hp[l].0 * hp[r - l].1 % m) % m)
            .fold(0, |a, b| a ^ b)
    }

    pub fn len(&self) -> usize {
        self.hash_pow_list
            .first()
            .map(|v| v.1.len() - 1)
            .unwrap_or(0)
    }
}