#853690 (Rust) No.1876 Xor of Sum

• 問題: No.1876 Xor of Sum
• ユーザー: koba-e964
• 提出日時: 2023-03-28 22:13:09
• 言語: Rust (1.77.0 + proconio)
• 結果: AC
• 実行時間: 316 ms / 2,000 ms
• コード長: 5,062 bytes
• コンパイル時間: 13,741 ms
• コンパイル使用メモリ: 378,132 KB
• 実行使用メモリ: 5,376 KB
• 最終ジャッジ日時: 2024-09-20 10:42:00
• 合計ジャッジ時間: 19,776 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	6 ms; 5,248 KB
testcase_01	AC	6 ms; 5,376 KB
testcase_02	AC	7 ms; 5,376 KB
testcase_03	AC	128 ms; 5,376 KB
testcase_04	AC	217 ms; 5,376 KB
testcase_05	AC	30 ms; 5,376 KB
testcase_06	AC	303 ms; 5,376 KB
testcase_07	AC	35 ms; 5,376 KB
testcase_08	AC	31 ms; 5,376 KB
testcase_09	AC	203 ms; 5,376 KB
testcase_10	AC	104 ms; 5,376 KB
testcase_11	AC	258 ms; 5,376 KB
testcase_12	AC	123 ms; 5,376 KB
testcase_13	AC	184 ms; 5,376 KB
testcase_14	AC	152 ms; 5,376 KB
testcase_15	AC	174 ms; 5,376 KB
testcase_16	AC	25 ms; 5,376 KB
testcase_17	AC	274 ms; 5,376 KB
testcase_18	AC	301 ms; 5,376 KB
testcase_19	AC	303 ms; 5,376 KB
testcase_20	AC	299 ms; 5,376 KB
testcase_21	AC	303 ms; 5,376 KB
testcase_22	AC	305 ms; 5,376 KB
testcase_23	AC	300 ms; 5,376 KB
testcase_24	AC	316 ms; 5,376 KB
testcase_25	AC	304 ms; 5,376 KB
testcase_26	AC	303 ms; 5,376 KB
testcase_27	AC	305 ms; 5,376 KB
testcase_28	AC	303 ms; 5,376 KB
testcase_29	AC	305 ms; 5,376 KB

ソースコード

// https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
macro_rules! input {
    ($($r:tt)*) => {
        let stdin = std::io::stdin();
        let mut bytes = std::io::Read::bytes(std::io::BufReader::new(stdin.lock()));
        let mut next = move || -> String{
            bytes.by_ref().map(|r|r.unwrap() as char)
                .skip_while(|c|c.is_whitespace())
                .take_while(|c|!c.is_whitespace())
                .collect()
        };
        input_inner!{next, $($r)*}
    };
}

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

macro_rules! read_value {
    ($next:expr, [ $t:tt ; $len:expr ]) => {
        (0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
    };
    ($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error"));
}

// Verified by https://atcoder.jp/contests/arc084/submissions/3935443
#[derive(Clone)]
struct BitSet {
    size: usize,
    buf: Vec<usize>,
}

impl BitSet {
    // size should be a multiple of bit-size of usize.
    fn new(size: usize) -> Self {
        let w = 8 * std::mem::size_of::<usize>();
        assert_eq!(size & (w - 1), 0);
        let count = size / w;
        BitSet {
            size: size,
            buf: vec![0; count],
        }
    }
    #[allow(unused)]
    fn set(&mut self, idx: usize, val: bool) {
        debug_assert!(idx < self.size);
        let w = 8 * std::mem::size_of::<usize>();
        let idx0 = idx / w;
        let idx1 = idx & (w - 1);
        if val {
            self.buf[idx0] |= 1 << idx1;
        } else {
            self.buf[idx0] &= !(1 << idx1);
        }
    }
    #[allow(unused)]
    fn get(&self, idx: usize) -> bool {
        let w = 8 * std::mem::size_of::<usize>();
        debug_assert!(idx < self.size);
        let idx0 = idx / w;
        let idx1 = idx & (w - 1);
        (self.buf[idx0] >> idx1 & 1) == 1
    }
    #[allow(unused)]
    fn shl(&self, val: usize) -> Self {
        if val >= self.size { return Self::new(self.size); }
        let w = 8 * std::mem::size_of::<usize>();
        let count = self.size / w;
        let sh0 = val / w;
        let sh1 = val & (w - 1);
        let mut ans = Self::new(self.size);
        if sh1 == 0 {
            for i in 0..count - sh0 {
                ans.buf[i + sh0] = self.buf[i];
            }
        } else {
            ans.buf[sh0] = self.buf[0] << sh1;
            for i in 1..count - sh0 {
                ans.buf[i + sh0] = self.buf[i] << sh1
                    | self.buf[i - 1] >> (w - sh1);
            }
        }
        ans
    }
    // Verified by: https://www.hackerrank.com/contests/yfkpo4/challenges/e-strange-clock/submissions/code/1357435235
    #[allow(unused)]
    fn shr(&self, val: usize) -> Self {
        if val >= self.size { return Self::new(self.size); }
        let w = 8 * std::mem::size_of::<usize>();
        let count = self.size / w;
        let sh0 = val / w;
        let sh1 = val & (w - 1);
        let mut ans = Self::new(self.size);
        if sh1 == 0 {
            for i in 0..count - sh0 {
                ans.buf[i] = self.buf[i + sh0];
            }
        } else {
            for i in 0..count - sh0 - 1 {
                ans.buf[i] = self.buf[i + sh0] >> sh1
                    | self.buf[i + sh0 + 1] << (w - sh1);
            }
            ans.buf[count - sh0 - 1] = self.buf[count - 1] >> sh1;
        }
        ans
    }
    #[allow(unused)]
    fn msb(&self) -> Option<usize> {
        let w = 8 * std::mem::size_of::<usize>();
        let count = self.size / w;
        for i in (0..count).rev() {
            let v = self.buf[i];
            if v != 0 {
                return Some(w * i + w - 1 - v.leading_zeros() as usize);
            }
        }
        None
    }
}

// TODO reference is not allowed as rhs
impl std::ops::BitXorAssign for BitSet {
    fn bitxor_assign(&mut self, other: BitSet) {
        debug_assert_eq!(self.size, other.size);
        for i in 0..self.buf.len() {
            self.buf[i] ^= other.buf[i];
        }
    }
}
impl std::ops::BitOrAssign for BitSet {
    fn bitor_assign(&mut self, other: BitSet) {
        debug_assert_eq!(self.size, other.size);
        for i in 0..self.buf.len() {
            self.buf[i] |= other.buf[i];
        }
    }
}

// https://yukicoder.me/problems/no/1876 (3)
// ナップサック問題で、それぞれの重みについてそれを実現する方法の総数の偶奇だけが分かれば良いことに注意すると、bitset で O(N \sum_i A_i/w)。
// Similar problems: https://atcoder.jp/contests/agc020/tasks/agc020_c
fn main() {
    input! {
        n: usize,
        a: [usize; n],
    }
    const W: usize = 4_000_064;
    let mut bs = BitSet::new(W);
    bs.set(0, true);
    for a in a {
        let tmp = bs.shl(a);
        bs ^= tmp;
    }
    let mut ans = 0;
    for i in 0..W {
        if bs.get(i) {
            ans ^= i;
        }
    }
    println!("{}", ans);
}