#264304 (Rust) No.697 池の数はいくつか

• 問題: No.697 池の数はいくつか
• ユーザー: くれちー
• 提出日時: 2018-06-09 20:24:52
• 言語: Rust (1.77.0 + proconio)
• 結果: AC
• 実行時間: 375 ms / 6,000 ms
• コード長: 5,346 bytes
• コンパイル時間: 13,307 ms
• コンパイル使用メモリ: 379,404 KB
• 実行使用メモリ: 19,584 KB
• 最終ジャッジ日時: 2024-11-08 07:37:13
• 合計ジャッジ時間: 18,073 ms
• ジャッジサーバーID （参考情報）: judge4 / judge2

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	1 ms; 5,248 KB
testcase_01	AC	1 ms; 5,248 KB
testcase_02	AC	1 ms; 5,248 KB
testcase_03	AC	1 ms; 5,248 KB
testcase_04	AC	1 ms; 5,248 KB
testcase_05	AC	1 ms; 5,248 KB
testcase_06	AC	1 ms; 5,248 KB
testcase_07	AC	1 ms; 5,248 KB
testcase_08	AC	1 ms; 5,248 KB
testcase_09	AC	1 ms; 5,248 KB
testcase_10	AC	1 ms; 5,248 KB
testcase_11	AC	1 ms; 5,248 KB
testcase_12	AC	1 ms; 5,248 KB
testcase_13	AC	1 ms; 5,248 KB
testcase_14	AC	1 ms; 5,248 KB
testcase_15	AC	1 ms; 5,248 KB
testcase_16	AC	1 ms; 5,248 KB
testcase_17	AC	1 ms; 5,248 KB
testcase_18	AC	1 ms; 5,248 KB
testcase_19	AC	1 ms; 5,248 KB
testcase_20	AC	1 ms; 5,248 KB
testcase_21	AC	1 ms; 5,248 KB
testcase_22	AC	1 ms; 5,248 KB
testcase_23	AC	1 ms; 5,248 KB
testcase_24	AC	42 ms; 5,248 KB
testcase_25	AC	42 ms; 5,248 KB
testcase_26	AC	43 ms; 5,248 KB
testcase_27	AC	41 ms; 5,248 KB
testcase_28	AC	42 ms; 5,248 KB
testcase_29	AC	318 ms; 19,456 KB
testcase_30	AC	368 ms; 19,456 KB
testcase_31	AC	313 ms; 19,456 KB
testcase_32	AC	367 ms; 19,456 KB
testcase_33	AC	369 ms; 19,456 KB
testcase_34	AC	375 ms; 19,584 KB

ソースコード

fn solve<R: BufRead, W: Write>(_reader: R, _writer: &mut W) {
  let mut _scanner = Scanner::new(_reader);

  #[allow(unused_macros)]
  macro_rules! scan {
    ($t:ty) => {
      _scanner.next::<$t>().unwrap()
    };
    ($($t:ty),+) => {
      ($(scan!($t)),+)
    };
    ($t:ty; $n:expr) => {
      scan_iter!($t; $n).collect::<Vec<_>>()
    };
    ($t_0:ty, $t_1:ty; $n:expr) => {
      scan!($t_0 = 0, $t_1 = 1; $n)
    };
    ($t_0:ty, $t_1:ty, $t_2:ty; $n:expr) => {
      scan!($t_0 = 0, $t_1 = 1, $t_2 = 2; $n)
    };
    ($($t:ty = $i:tt),+; $n:expr) => {{
      let mut vecs = ($(Vec::<$t>::with_capacity($n)),+);
      for _ in 0..$n {$(
        vecs.$i.push(scan!($t));
      )+}
      vecs
    }};
  }

  #[allow(unused_macros)]
  macro_rules! scan_iter {
    ($t:ty; $n:expr) => {
      _scanner.take::<$t>($n).map(|x| x.unwrap())
    };
  }

  #[allow(unused_macros)]
  macro_rules! print {
    ($fmt:expr) => {
      write!(_writer, $fmt).unwrap()
    };
    ($fmt:expr, $($arg:tt)*) => {
      write!(_writer, $fmt, $($arg)*).unwrap()
    };
  }

  #[allow(unused_macros)]
  macro_rules! println {
    () => {
      writeln!(_writer).unwrap()
    };
    ($fmt:expr) => {
      writeln!(_writer, $fmt).unwrap()
    };
    ($fmt:expr, $($arg:tt)*) => {
      writeln!(_writer, $fmt, $($arg)*).unwrap()
    };
  }

  use std::collections::VecDeque;

  const DY: [i32; 4] = [0, 1, 0, -1];
  const DX: [i32; 4] = [1, 0, -1, 0];

  let (h, w) = scan!(usize, usize);
  let field = scan_iter!(u8; h * w).map(|x| x == b'1').collect::<Vec<_>>();

  let mut visited = vec![false; h * w];
  let mut queue = VecDeque::<(i32, i32)>::new();
  let (h, w) = (h as i32, w as i32);
  let index = |y, x| (y * w + x) as usize;
  let mut ans = 0;

  for i in 0..h {
    for j in 0..w {
      if field[index(i, j)] && !visited[index(i, j)] {
        queue.push_back((i, j));
        while let Some((y, x)) = queue.pop_front() {
          for (&dy, &dx) in DY.iter().zip(DX.iter()) {
            let y = y + dy;
            let x = x + dx;
            if 0 <= y && y < h && 0 <= x && x < w && field[index(y, x)] {
              if !visited[index(y, x)] {
                visited[index(y, x)] = true;
                queue.push_back((y, x));
              }
            }
          }
        }
        ans += 1;
      }
    }
  }

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

fn main() {
  let stdin = stdin();
  let stdout = stdout();
  #[cfg(debug_assertions)]
  let mut writer = stdout.lock();
  #[cfg(not(debug_assertions))]
  let mut writer = ::std::io::BufWriter::new(stdout.lock());
  solve(stdin.lock(), &mut writer);
  writer.flush().unwrap();
}

use io::Scanner;
use std::io::{stdin, stdout, BufRead, Write};

pub mod io {
  pub use self::scanner::*;

  mod scanner {
    use std::io::BufRead;
    use std::marker::PhantomData;
    use std::str::{from_utf8, FromStr};

    pub struct Scanner<R> {
      reader: R,
      buffer: Vec<u8>,
      position: usize,
    }

    impl<R: BufRead> Scanner<R> {
      pub fn new(reader: R) -> Self {
        Scanner { reader: reader, buffer: vec![], position: 0 }
      }

      pub fn next<T: Parse>(&mut self) -> Option<T> {
        Parse::parse(self.next_bytes().unwrap_or(&[]))
      }

      pub fn take<T: Parse>(&mut self, n: usize) -> Take<R, T> {
        Take { scanner: self, n: n, _marker: PhantomData }
      }

      pub fn next_bytes(&mut self) -> Option<&[u8]> {
        if self.buffer.is_empty() {
          self.read_line();
        }
        loop {
          match self.buffer.get(self.position) {
            Some(&b' ') => self.position += 1,
            Some(&b'\n') => self.read_line(),
            Some(_) => break,
            None => return None,
          }
        }
        let start = self.position;
        loop {
          match self.buffer.get(self.position) {
            Some(&b' ') | Some(&b'\n') | None => break,
            Some(_) => self.position += 1,
          }
        }
        Some(&self.buffer[start..self.position])
      }

      fn read_line(&mut self) {
        self.position = 0;
        self.buffer.clear();
        self.reader.read_until(b'\n', &mut self.buffer).unwrap();
      }
    }

    pub struct Take<'a, R: 'a, T> {
      scanner: &'a mut Scanner<R>,
      n: usize,
      _marker: PhantomData<fn() -> T>,
    }

    impl<'a, R: BufRead, T: Parse> Iterator for Take<'a, R, T> {
      type Item = Option<T>;

      fn next(&mut self) -> Option<Self::Item> {
        if self.n > 0 {
          self.n -= 1;
          Some(self.scanner.next())
        } else {
          None
        }
      }

      fn size_hint(&self) -> (usize, Option<usize>) {
        (self.n, Some(self.n))
      }
    }

    impl<'a, R: BufRead, T: Parse> ExactSizeIterator for Take<'a, R, T> {}

    pub trait Parse: Sized {
      fn parse(bytes: &[u8]) -> Option<Self>;
    }

    impl Parse for u8 {
      fn parse(bytes: &[u8]) -> Option<Self> {
        if bytes.len() == 1 {
          Some(*unsafe { bytes.get_unchecked(0) })
        } else {
          None
        }
      }
    }

    macro_rules! parse_impl {
      ($($t:ident)+) => {$(
        impl Parse for $t {
          fn parse(bytes: &[u8]) -> Option<Self> {
            from_utf8(bytes).ok().and_then(|s| $t::from_str(s).ok())
          }
        }
      )+};
    }

    parse_impl! { i32 i64 isize u32 u64 usize String }
  }
}