#348920 (Rust) No.482 あなたの名は

• 問題: No.482 あなたの名は
• ユーザー: MasuqaT
• 提出日時: 2019-05-25 21:12:12
• 言語: Rust (1.77.0 + proconio)
• 結果: AC
• 実行時間: 8 ms / 2,000 ms
• コード長: 4,564 bytes
• コンパイル時間: 16,954 ms
• コンパイル使用メモリ: 381,100 KB
• 実行使用メモリ: 6,944 KB
• 最終ジャッジ日時: 2024-09-17 15:06:58
• 合計ジャッジ時間: 16,091 ms
• ジャッジサーバーID （参考情報）: judge1 / judge3

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	0 ms; 6,812 KB
testcase_01	AC	1 ms; 6,812 KB
testcase_02	AC	1 ms; 6,812 KB
testcase_03	AC	1 ms; 6,940 KB
testcase_04	AC	1 ms; 6,944 KB
testcase_05	AC	1 ms; 6,940 KB
testcase_06	AC	0 ms; 6,944 KB
testcase_07	AC	0 ms; 6,940 KB
testcase_08	AC	1 ms; 6,944 KB
testcase_09	AC	0 ms; 6,940 KB
testcase_10	AC	0 ms; 6,940 KB
testcase_11	AC	1 ms; 6,940 KB
testcase_12	AC	1 ms; 6,940 KB
testcase_13	AC	1 ms; 6,940 KB
testcase_14	AC	0 ms; 6,940 KB
testcase_15	AC	8 ms; 6,940 KB
testcase_16	AC	8 ms; 6,940 KB
testcase_17	AC	8 ms; 6,940 KB
testcase_18	AC	8 ms; 6,940 KB
testcase_19	AC	8 ms; 6,940 KB
testcase_20	AC	8 ms; 6,944 KB
testcase_21	AC	8 ms; 6,940 KB
testcase_22	AC	8 ms; 6,944 KB
testcase_23	AC	8 ms; 6,944 KB
testcase_24	AC	8 ms; 6,944 KB
testcase_25	AC	8 ms; 6,944 KB
testcase_26	AC	8 ms; 6,940 KB
testcase_27	AC	8 ms; 6,944 KB
testcase_28	AC	8 ms; 6,940 KB
testcase_29	AC	7 ms; 6,940 KB
testcase_30	AC	1 ms; 6,940 KB

コンパイルメッセージ

warning: unused `Result` that must be used
   --> src/main.rs:175:5
    |
175 |     write!(writer, "{}", if is_feasible { "YES" } else { "NO" });
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: this `Result` may be an `Err` variant, which should be handled
    = note: `#[warn(unused_must_use)]` on by default
    = note: this warning originates in the macro `write` (in Nightly builds, run with -Z macro-backtrace for more info)

ソースコード

use std::io;
use std::io::{BufRead, Write};
use std::ops::{Rem, Div, Mul};

macro_rules! input {
    (source = $s:expr, $($r:tt)*) => {
        let mut iter = $s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
    (stdin = $s:expr, $($r:tt)*) => {
        let s = {
            let mut s = String::new();
            $s.read_to_string(&mut s).unwrap();
            s
        };
        let mut iter = s.split_whitespace();
        input_inner!{iter, $($r)*}
    };
}

macro_rules! input_inner {
    ($iter:expr) => {};
    ($iter:expr, ) => {};

    ($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
        let $var = read_value!($iter, $t);
        input_inner!{$iter $($r)*}
    };
}

macro_rules! read_value {
    ($iter:expr, ( $($t:tt),* )) => {
        ( $(read_value!($iter, $t)),* )
    };

    ($iter:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
    };

    ($iter:expr, chars) => {
        read_value!($iter, String).chars().collect::<Vec<char>>()
    };

    ($iter:expr, usize1) => {
        read_value!($iter, usize) - 1
    };

    ($iter:expr, $t:ty) => {
        $iter.next().unwrap().parse::<$t>().expect("Parse error")
    };
}

#[allow(unused_macros)]
macro_rules! assert_judge {
    ($method:ident, $input:expr, $expected:expr) => {
        {
            let input = $input.as_bytes();
            let mut output = Vec::new();

            $method(&input[..], &mut output);

            let output = String::from_utf8(output).expect("Not UTF-8");

            assert_eq!($expected, output);
        }
    };
}

#[allow(unused_macros)]
macro_rules! assert_judge_with_output {
    ($method:ident, $input:expr) => {
        {
            let input = $input.as_bytes();
            let mut output = Vec::new();

            $method(&input[..], &mut output);

            String::from_utf8(output).expect("Not UTF-8")
        }
    };
}

#[allow(unused_macros)]
macro_rules! assert_eq_with_error {
    ($left:expr, $right:expr, $precision:expr) => ({
        match (&$left, &$right, &$precision) {
            (left_val, right_val, precision_val) => {
                if !(*left_val - *precision_val < *right_val && *right_val < *left_val + *precision_val) {
                    // The reborrows below are intentional. Without them, the stack slot for the
                    // borrow is initialized even before the values are compared, leading to a
                    // noticeable slow down.
                    panic!(r#"assertion failed: `(left == right) +- precision`
      left: `{:?}`,
     right: `{:?}`,
 precision: `{:?}`"#, &*left_val, &*right_val, &*precision_val)
                }
            }
        }
    });
}

trait GenericInteger: Copy + PartialEq + Rem<Output=Self> + Div<Output=Self> + Mul<Output=Self> {
    fn zero() -> Self;
}

macro_rules! dec_gi {
    () => {};
    ($t:ty $(, $r:ty)*) => {
        impl GenericInteger for $t {
            fn zero() -> Self { 0 }
        }

        dec_gi![ $( $r ),* ];
    };
}

dec_gi![u8, u16, u32, u64, u128, usize, i8, i16, i32, i64, i128, isize];

#[allow(dead_code)]
fn gcd<T>(a: T, b: T) -> T where T: GenericInteger {
    if b == T::zero() {
        a
    } else {
        gcd(b, a % b)
    }
}

#[allow(dead_code)]
fn lcm<T>(a: T, b: T) -> T where T: GenericInteger {
    a / gcd(a, b) * b
}

#[allow(unused_macros)]
macro_rules! swap {
    ($v1:expr, $v2:expr) => {
        let buf = $v1;
        $v1 = $v2;
        $v2 = buf;
    };
}

fn main() {
    let stdio = io::stdin();
    let input = stdio.lock();

    let output = io::stdout();

    process(input, output);
}

fn process<R, W>(mut reader: R, mut writer: W) -> () where
    R: BufRead,
    W: Write {
    input! {
        stdin = reader,
        n: usize, k: usize,
        d: [usize; n]
    }

    let mut d: Vec<usize> = d;

    // symmetric group
    // extra 2n steps is okay

    let mut counter = 0;
    for i in 0..n {
        while d[i] != i + 1 {
            let current = d[i] - 1;
            swap!(d[i], d[current]);
            counter += 1;
        }
    }

    let is_feasible = counter == k || (k > counter && (k - counter) % 2 == 0);
    write!(writer, "{}", if is_feasible { "YES" } else { "NO" });
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn sample1() {
        assert_judge!(process,
"
2 1
2 1
", "YES");
    }

    #[test]
    fn sample2() {
        assert_judge!(process,
"
3 2
3 2 1
", "NO");
    }


    #[test]
    fn sample3() {
        assert_judge!(process,
"
4 2
1 2 3 4
", "YES");
    }
}