結果

問題 No.464 PPAP
コンテスト
ユーザー hatoo
提出日時 2017-11-06 15:36:22
言語 Rust
(1.83.0 + proconio)
結果
AC  
実行時間 1,397 ms / 2,000 ms
コード長 4,318 bytes
コンパイル時間 14,592 ms
コンパイル使用メモリ 377,964 KB
実行使用メモリ 5,248 KB
最終ジャッジ日時 2024-11-24 03:08:33
合計ジャッジ時間 17,580 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 4
other AC * 22
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: unused variable: `c`
   --> src/main.rs:158:15
    |
158 |         for (&c, i) in s[p + 1..].iter().zip(1..) {
    |               ^ help: if this is intentional, prefix it with an underscore: `_c`
    |
    = note: `#[warn(unused_variables)]` on by default

ソースコード

diff # 

#[allow(unused_imports)]
use std::cmp::{max, min, Ordering};
#[allow(unused_imports)]
use std::collections::{HashMap, HashSet, BinaryHeap, VecDeque};
#[allow(unused_imports)]
use std::iter::FromIterator;

mod util {
    use std::io::stdin;
    use std::str::FromStr;
    use std::fmt::Debug;

    #[allow(dead_code)]
    pub fn line() -> String {
        let mut line: String = String::new();
        stdin().read_line(&mut line).unwrap();
        line.trim().to_string()
    }

    #[allow(dead_code)]
    pub fn get<T: FromStr>() -> T
    where
        <T as FromStr>::Err: Debug,
    {
        let mut line: String = String::new();
        stdin().read_line(&mut line).unwrap();
        line.trim().parse().unwrap()
    }

    #[allow(dead_code)]
    pub fn gets<T: FromStr>() -> Vec<T>
    where
        <T as FromStr>::Err: Debug,
    {
        let mut line: String = String::new();
        stdin().read_line(&mut line).unwrap();
        line.split_whitespace()
            .map(|t| t.parse().unwrap())
            .collect()
    }

    #[allow(dead_code)]
    pub fn get2<T: FromStr, U: FromStr>() -> (T, U)
    where
        <T as FromStr>::Err: Debug,
        <U as FromStr>::Err: Debug,
    {
        let mut line: String = String::new();
        stdin().read_line(&mut line).unwrap();
        let mut iter = line.split_whitespace();
        (
            iter.next().unwrap().parse().unwrap(),
            iter.next().unwrap().parse().unwrap(),
        )
    }

    #[allow(dead_code)]
    pub fn get3<S: FromStr, T: FromStr, U: FromStr>() -> (S, T, U)
    where
        <S as FromStr>::Err: Debug,
        <T as FromStr>::Err: Debug,
        <U as FromStr>::Err: Debug,
    {
        let mut line: String = String::new();
        stdin().read_line(&mut line).unwrap();
        let mut iter = line.split_whitespace();
        (
            iter.next().unwrap().parse().unwrap(),
            iter.next().unwrap().parse().unwrap(),
            iter.next().unwrap().parse().unwrap(),
        )
    }
}

#[allow(unused_macros)]
macro_rules! debug {
    ($x: expr) => {
        println!("{}: {:?}", stringify!($x), $x)
    }
}

/*
struct Manacher<'a, T: 'a + Eq> {
    s: &'a [T],
    r: Vec<usize>,
}

impl<'a, T: 'a + Eq> Manacher<'a, T> {
    fn new(seq: &'a [T]) -> Manacher<'a, T> {
        let mut r = vec![0; 2 * seq.len() - 1];
        let mut i = 0;
        let mut j = 0;
        while i < r.len() {
            while i >= j && i + j < r.len() && Self::get(seq, i - j) == Self::get(seq, i + j) {
                j += 1;
            }
            r[i] = j;
            let mut k = 1;
            while i >= k && i + k < r.len() && k + r[i - k] < j {
                r[i + k] = r[i - k];
                k += 1;
            }
            i += k;
            j -= k;
        }

        Manacher { s: seq, r: r }
    }

    // [l,r]
    fn is_palindrome(&self, l: usize, r: usize) -> bool {
        self.r[l + r] >= r - l + 1
    }

    fn get(s: &[T], i: usize) -> Option<&T> {
        if i & 1 == 1 { None } else { s.get(i) }
    }
}
*/

fn main() {
    let s: Vec<char> = util::line().chars().collect();
    let s_rev: Vec<char> = s.iter().cloned().rev().collect();
    let mut front = Vec::new();
    let mut back = Vec::new();

    {
        let mut a = VecDeque::new();
        let mut b = VecDeque::new();

        for (i, &c) in s.iter().enumerate() {
            a.push_front(c);
            b.push_back(c);

            if a == b {
                front.push(i);
            }
        }
    }

    {
        let mut a = VecDeque::new();
        let mut b = VecDeque::new();

        for (i, &c) in s.iter().enumerate().rev() {
            a.push_front(c);
            b.push_back(c);

            if a == b {
                back.push(i);
            }
        }
    }

    let mut ans = 0;
    back.sort();
    for &p in &front {
        for (&c, i) in s[p + 1..].iter().zip(1..) {
            if &s[p + 1..p + 2 + i / 2] ==
                &s_rev[s.len() - p - i - 1..s.len() - p - 1 - (i - 1) / 2]
            {
                ans += back.len() as u64 -
                    match back.binary_search(&(p + i as usize + 2)) {
                        Ok(x) => x as u64,
                        Err(x) => x as u64,
                    };
            }
        }

    }
    println!("{}", ans);

}
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