#565123 (Rust) No.1255 ハイレーツ・オブ・ボリビアン

• 問題: No.1255 ハイレーツ・オブ・ボリビアン
• ユーザー: cotton_fn_
• 提出日時: 2020-10-09 23:10:57
• 言語: Rust (1.77.0)
• 結果: AC
• 実行時間: 471 ms / 2,000 ms
• コード長: 5,935 bytes
• コンパイル時間: 3,077 ms
• コンパイル使用メモリ: 161,848 KB
• 実行使用メモリ: 4,380 KB
• 最終ジャッジ日時: 2023-09-30 14:44:19
• 合計ジャッジ時間: 4,745 ms
• ジャッジサーバーID （参考情報）: judge15 / judge12

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; 4,376 KB
testcase_02	AC	1 ms; 4,380 KB
testcase_03	AC	1 ms; 4,376 KB
testcase_04	AC	2 ms; 4,376 KB
testcase_05	AC	3 ms; 4,380 KB
testcase_06	AC	4 ms; 4,376 KB
testcase_07	AC	4 ms; 4,380 KB
testcase_08	AC	234 ms; 4,380 KB
testcase_09	AC	240 ms; 4,376 KB
testcase_10	AC	234 ms; 4,380 KB
testcase_11	AC	236 ms; 4,380 KB
testcase_12	AC	243 ms; 4,380 KB
testcase_13	AC	20 ms; 4,380 KB
testcase_14	AC	471 ms; 4,380 KB
testcase_15	AC	224 ms; 4,376 KB

コンパイルメッセージ

warning: unused label
  --> Main.rs:31:5
   |
31 |     'test: for _ in 0..t {
   |     ^^^^^
   |
   = note: `#[warn(unused_labels)]` on by default

warning: 1 warning emitted

ソースコード

#![allow(unused_imports, unused_macros)]

use kyoproio::*;
use std::{
    collections::*,
    io::{self, prelude::*},
    iter,
    mem::{replace, swap},
};

fn main() -> io::Result<()> {
    std::thread::Builder::new()
        .stack_size(64 * 1024 * 1024)
        .spawn(|| {
            let stdin = io::stdin();
            let stdout = io::stdout();
            run(KInput::new(stdin.lock()), io::BufWriter::new(stdout.lock()))
        })?
        .join()
        .unwrap()
}

fn run<I: Input, O: Write>(mut kin: I, mut out: O) -> io::Result<()> {
    macro_rules! output { ($($args:expr),+) => { write!(&mut out, $($args),+)?; }; }
    macro_rules! outputln {
        ($($args:expr),+) => { output!($($args),+); outputln!(); };
        () => { output!("\n"); if cfg!(debug_assertions) { out.flush()?; } }
    }

    let t: usize = kin.input();
    'test: for _ in 0..t {
        let n: i64 = kin.input();
        if n == 1 {
            outputln!("1");
            continue;
        }
        let m = 2 * n - 1;
        let ans = discrete_log(2, 1, m).unwrap_or(-1);
        outputln!("{}", ans);
        /*
        let h = (n as f64).sqrt().ceil() as i64 + 5;
        let mut map = HashMap::new();
        let mut x = 1;
        for i in 0..h {
            if i > 0 && x == 1 {
                outputln!("{}", i);
                continue 'test;
            }
            map.insert(x, i);
            x = 2 * x % m;
        }
        // x == 2^h (mod m)
        let k = x;
        for i in 1..=h {
            // 2^hi == 2^j
            // 2^(hi - j) == 1
            if let Some(j) = map.get(&x) {
                assert_eq!(mod_pow(2, h * i - j, m), 1);
                outputln!("{}", h * i - j);
                continue 'test;
            }
            x = k * x % m;
        }
        outputln!("-1");
        */
    }

    Ok(())
}

pub fn mod_pow(mut a: i64, mut b: i64, m: i64) -> i64 {
    let mut y = 1;
    while b > 0 {
        if b & 1 == 1 {
            y = y * a % m;
        }
        a = a * a % m;
        b >>= 1;
    }
    y
}

pub fn discrete_log(a: i64, b: i64, m: i64) -> Option<i64> {
    if m == 1 {
        return Some(0);
    }
    let n = (m as f64).sqrt().ceil() as i64 + 100;
    let mut baby = 1;
    let mut map = HashMap::new();
    for i in 0..n {
        if i > 0 && baby == b {
            return Some(i);
        }
        map.insert((b * baby).rem_euclid(m), i);
        baby = (baby * a).rem_euclid(m);
    }
    let mut giant = 1;
    for i in 1..=n {
        giant = (giant * baby).rem_euclid(m);
        if let Some(j) = map.get(&giant) {
            let ans = n * i - j;
            return if mod_pow(a, ans, m) == b {
                Some(ans)
            } else {
                None
            };
        }
    }
    None
}

// -----------------------------------------------------------------------------
pub mod kyoproio {
    use std::io::prelude::*;
    pub trait Input {
        fn str(&mut self) -> &str;
        fn input<T: InputParse>(&mut self) -> T {
            T::input(self)
        }
        fn iter<T: InputParse>(&mut self) -> Iter<T, Self> {
            Iter(self, std::marker::PhantomData)
        }
        fn seq<T: InputParse, B: std::iter::FromIterator<T>>(&mut self, n: usize) -> B {
            self.iter().take(n).collect()
        }
    }
    pub struct KInput<R> {
        src: R,
        buf: String,
        pos: usize,
    }
    impl<R: BufRead> KInput<R> {
        pub fn new(src: R) -> Self {
            Self {
                src,
                buf: String::with_capacity(1024),
                pos: 0,
            }
        }
    }
    impl<R: BufRead> Input for KInput<R> {
        fn str(&mut self) -> &str {
            loop {
                if self.pos >= self.buf.len() {
                    self.pos = 0;
                    self.buf.clear();
                    if self.src.read_line(&mut self.buf).expect("io error") == 0 {
                        return &self.buf;
                    }
                }
                let range = self.pos
                    ..self.buf[self.pos..]
                        .find(|c: char| c.is_ascii_whitespace())
                        .map(|i| i + self.pos)
                        .unwrap_or_else(|| self.buf.len());
                self.pos = range.end + 1;
                if range.end > range.start {
                    return &self.buf[range];
                }
            }
        }
    }
    pub struct Iter<'a, T, I: ?Sized>(&'a mut I, std::marker::PhantomData<*const T>);
    impl<'a, T: InputParse, I: Input + ?Sized> Iterator for Iter<'a, T, I> {
        type Item = T;
        fn next(&mut self) -> Option<T> {
            Some(self.0.input())
        }
    }
    pub trait InputParse: Sized {
        fn input<I: Input + ?Sized>(src: &mut I) -> Self;
    }
    impl InputParse for Vec<u8> {
        fn input<I: Input + ?Sized>(src: &mut I) -> Self {
            src.str().as_bytes().to_owned()
        }
    }
    macro_rules! from_str_impl {
        { $($T:ty)* } => {
            $(impl InputParse for $T {
                fn input<I: Input + ?Sized>(src: &mut I) -> Self {
                    src.str().parse::<$T>().expect("parse error")
                }
            })*
        }
    }
    from_str_impl! {
        String char bool f32 f64 isize i8 i16 i32 i64 i128 usize u8 u16 u32 u64 u128
    }
    macro_rules! tuple_impl {
        ($H:ident $($T:ident)*) => {
            impl<$H: InputParse, $($T: InputParse),*> InputParse for ($H, $($T),*) {
                fn input<I: Input + ?Sized>(src: &mut I) -> Self {
                    ($H::input(src), $($T::input(src)),*)
                }
            }
            tuple_impl!($($T)*);
        };
        () => {}
    }
    tuple_impl!(A B C D E F G);
    #[macro_export]
    macro_rules! kdbg {
        ($($v:expr),*) => {
            if cfg!(debug_assertions) { dbg!($($v),*) } else { ($($v),*) }
        }
    }
}