結果

問題 No.1300 Sum of Inversions
ユーザー fukafukatanifukafukatani
提出日時 2020-11-27 23:42:58
言語 Rust
(1.77.0)
結果
AC  
実行時間 695 ms / 2,000 ms
コード長 8,757 bytes
コンパイル時間 2,211 ms
コンパイル使用メモリ 174,464 KB
実行使用メモリ 30,596 KB
最終ジャッジ日時 2023-10-09 21:20:39
合計ジャッジ時間 20,567 ms
ジャッジサーバーID
（参考情報） 		judge11 / judge12
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 1 ms
4,348 KB
testcase_01 AC 1 ms
4,352 KB
testcase_02 AC 1 ms
4,352 KB
testcase_03 AC 543 ms
27,000 KB
testcase_04 AC 539 ms
26,684 KB
testcase_05 AC 422 ms
20,056 KB
testcase_06 AC 624 ms
28,584 KB
testcase_07 AC 594 ms
27,984 KB
testcase_08 AC 645 ms
29,256 KB
testcase_09 AC 658 ms
29,360 KB
testcase_10 AC 312 ms
16,564 KB
testcase_11 AC 307 ms
16,664 KB
testcase_12 AC 516 ms
26,816 KB
testcase_13 AC 500 ms
26,400 KB
testcase_14 AC 695 ms
30,508 KB
testcase_15 AC 621 ms
29,112 KB
testcase_16 AC 529 ms
27,956 KB
testcase_17 AC 300 ms
16,304 KB
testcase_18 AC 340 ms
17,152 KB
testcase_19 AC 444 ms
25,332 KB
testcase_20 AC 459 ms
25,604 KB
testcase_21 AC 450 ms
25,476 KB
testcase_22 AC 395 ms
20,080 KB
testcase_23 AC 587 ms
28,480 KB
testcase_24 AC 409 ms
20,380 KB
testcase_25 AC 337 ms
16,908 KB
testcase_26 AC 331 ms
16,868 KB
testcase_27 AC 377 ms
19,804 KB
testcase_28 AC 634 ms
29,704 KB
testcase_29 AC 437 ms
25,484 KB
testcase_30 AC 624 ms
29,172 KB
testcase_31 AC 379 ms
20,276 KB
testcase_32 AC 418 ms
20,596 KB
testcase_33 AC 32 ms
11,180 KB
testcase_34 AC 39 ms
11,260 KB
testcase_35 AC 435 ms
30,596 KB
testcase_36 AC 438 ms
30,596 KB
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: associated function `set_modulus` is never used
  --> Main.rs:91:8
   |
91 |     fn set_modulus(m: i64) {
   |        ^^^^^^^^^^^
   |
   = note: `#[warn(dead_code)]` on by default

warning: associated function `pow` is never used
   --> Main.rs:109:8
    |
109 |     fn pow(self, p: i64) -> Modulo {
    |        ^^^

warning: associated function `inv` is never used
   --> Main.rs:121:8
    |
121 |     fn inv(self) -> Modulo {
    |        ^^^

warning: 3 warnings emitted

ソースコード

diff # 

#![allow(unused_imports)]
use std::cmp::*;
use std::collections::*;
use std::io::Write;
use std::ops::Bound::*;

#[allow(unused_macros)]
macro_rules! debug {
    ($($e:expr),*) => {
        #[cfg(debug_assertions)]
        $({
            let (e, mut err) = (stringify!($e), std::io::stderr());
            writeln!(err, "{} = {:?}", e, $e).unwrap()
        })*
    };
}

fn main() {
    let n = read::<usize>();
    let a = read_vec::<i64>()
        .iter()
        .map(|&x| Modulo(x))
        .collect::<Vec<_>>();

    let mut a_clone = a.clone();
    a_clone.sort();
    a_clone.dedup();

    let mut compress_dict = HashMap::new();
    for i in 0..a_clone.len() {
        compress_dict.insert(a_clone[i], i);
    }

    let mut from_left = vec![Modulo(0); n];
    let mut from_left_count = vec![0i64; n];
    let mut seg = SegTree::new(compress_dict.len(), Modulo(0), |a, b| a + b);
    let mut seg_count = SegTree::new(compress_dict.len(), 0, |a, b| a + b);
    for i in 0..n {
        let cur = compress_dict[&a[i]];
        from_left[i] = seg.query(cur + 1, compress_dict.len());
        let val = seg.query(cur, cur + 1);
        seg.update(cur, val + a[i]);

        from_left_count[i] = seg_count.query(cur + 1, compress_dict.len());
        let val = seg_count.query(cur, cur + 1);
        seg_count.update(cur, val + 1);
    }

    let mut from_right = vec![Modulo(0); n];
    let mut from_right_count = vec![0i64; n];
    let mut seg = SegTree::new(compress_dict.len(), Modulo(0), |a, b| a + b);
    let mut seg_count = SegTree::new(compress_dict.len(), 0, |a, b| a + b);
    for i in (0..n).rev() {
        let cur = compress_dict[&a[i]];
        from_right[i] = seg.query(0, cur);
        let val = seg.query(cur, cur + 1);
        seg.update(cur, val + a[i]);

        from_right_count[i] = seg_count.query(0, cur);
        let val = seg_count.query(cur, cur + 1);
        seg_count.update(cur, val + 1);
    }
    // debug!(from_left);
    // debug!(from_right);

    let mut ans = Modulo(0);
    for i in 0..n {
        ans += from_left[i] * from_right_count[i];
        ans += from_right[i] * from_left_count[i];
        ans += a[i] * from_right_count[i] * from_left_count[i];
    }
    println!("{}", ans);
}

fn read<T: std::str::FromStr>() -> T {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    s.trim().parse().ok().unwrap()
}

fn read_vec<T: std::str::FromStr>() -> Vec<T> {
    read::<String>()
        .split_whitespace()
        .map(|e| e.parse().ok().unwrap())
        .collect()
}
#[derive(Clone, Copy, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd)]
struct Modulo(i64);
static mut MODULUS: i64 = 998244353;
impl Modulo {
    fn set_modulus(m: i64) {
        unsafe {
            MODULUS = m;
        }
    }
    fn get_modulus() -> i64 {
        unsafe { MODULUS }
    }
    fn new(x: i64) -> Modulo {
        let m = Modulo::get_modulus();
        if x < 0 {
            Modulo(x % m + m)
        } else if x < m {
            Modulo(x)
        } else {
            Modulo(x % m)
        }
    }
    fn pow(self, p: i64) -> Modulo {
        if p == 0 {
            Modulo(1)
        } else {
            let mut t = self.pow(p / 2);
            t *= t;
            if p & 1 == 1 {
                t *= self;
            }
            t
        }
    }
    fn inv(self) -> Modulo {
        self.pow(Modulo::get_modulus() - 2)
    }
}
impl std::fmt::Display for Modulo {
    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
        self.0.fmt(f)
    }
}
impl std::ops::AddAssign for Modulo {
    fn add_assign(&mut self, other: Modulo) {
        let m = Modulo::get_modulus();
        self.0 += other.0;
        if self.0 >= m {
            self.0 -= m;
        }
    }
}
impl std::ops::MulAssign for Modulo {
    fn mul_assign(&mut self, other: Modulo) {
        let m = Modulo::get_modulus();
        self.0 *= other.0;
        self.0 %= m;
    }
}
impl std::ops::SubAssign for Modulo {
    fn sub_assign(&mut self, other: Modulo) {
        let m = Modulo::get_modulus();
        self.0 += m - other.0;
        if self.0 >= m {
            self.0 -= m;
        }
    }
}
macro_rules! impl_modulo_ops {
    ($imp:ident, $method:ident, $assign_imp:ident, $assign_method:ident) => {
        impl<'a> std::ops::$assign_imp<&'a Modulo> for Modulo {
            fn $assign_method(&mut self, other: &'a Modulo) {
                std::ops::$assign_imp::$assign_method(self, *other);
            }
        }
        impl std::ops::$imp for Modulo {
            type Output = Modulo;
            fn $method(self, other: Modulo) -> Modulo {
                let mut x = self;
                std::ops::$assign_imp::$assign_method(&mut x, other);
                x
            }
        }
        impl<'a> std::ops::$imp<Modulo> for &'a Modulo {
            type Output = Modulo;
            fn $method(self, other: Modulo) -> Modulo {
                std::ops::$imp::$method(*self, other)
            }
        }
        impl<'a> std::ops::$imp<&'a Modulo> for Modulo {
            type Output = Modulo;
            fn $method(self, other: &'a Modulo) -> Modulo {
                std::ops::$imp::$method(self, *other)
            }
        }
        impl<'a, 'b> std::ops::$imp<&'b Modulo> for &'a Modulo {
            type Output = Modulo;
            fn $method(self, other: &'b Modulo) -> Modulo {
                std::ops::$imp::$method(*self, *other)
            }
        }
        impl std::ops::$assign_imp<i64> for Modulo {
            fn $assign_method(&mut self, other: i64) {
                std::ops::$assign_imp::$assign_method(self, Modulo::new(other));
            }
        }
        impl<'a> std::ops::$assign_imp<&'a i64> for Modulo {
            fn $assign_method(&mut self, other: &'a i64) {
                std::ops::$assign_imp::$assign_method(self, *other);
            }
        }
        impl std::ops::$imp<i64> for Modulo {
            type Output = Modulo;
            fn $method(self, other: i64) -> Modulo {
                let mut x = self;
                std::ops::$assign_imp::$assign_method(&mut x, other);
                x
            }
        }
        impl<'a> std::ops::$imp<&'a i64> for Modulo {
            type Output = Modulo;
            fn $method(self, other: &'a i64) -> Modulo {
                std::ops::$imp::$method(self, *other)
            }
        }
        impl<'a> std::ops::$imp<i64> for &'a Modulo {
            type Output = Modulo;
            fn $method(self, other: i64) -> Modulo {
                std::ops::$imp::$method(*self, other)
            }
        }
        impl<'a, 'b> std::ops::$imp<&'b i64> for &'a Modulo {
            type Output = Modulo;
            fn $method(self, other: &'b i64) -> Modulo {
                std::ops::$imp::$method(*self, *other)
            }
        }
    };
}
impl_modulo_ops!(Add, add, AddAssign, add_assign);
impl_modulo_ops!(Mul, mul, MulAssign, mul_assign);
impl_modulo_ops!(Sub, sub, SubAssign, sub_assign);

use std::iter::Sum;
impl Sum for Modulo {
    fn sum<I>(iter: I) -> Self
    where
        I: Iterator<Item = Modulo>,
    {
        iter.fold(Modulo(0), |a, b| a + b)
    }
}

impl<'a> Sum<&'a Modulo> for Modulo {
    fn sum<I>(iter: I) -> Self
    where
        I: Iterator<Item = &'a Self>,
    {
        iter.fold(Modulo(0), |a, b| a + b)
    }
}

#[derive(Clone)]
struct SegTree<T, F>
where
    F: Fn(T, T) -> T,
    T: std::clone::Clone + std::marker::Copy,
{
    n: usize,
    dat: Vec<T>,
    init: T,
    functor: F,
}

impl<T, F> SegTree<T, F>
where
    F: Fn(T, T) -> T,
    T: std::clone::Clone + std::marker::Copy,
{
    fn new(n: usize, init: T, f: F) -> SegTree<T, F> {
        let mut m = 1;
        // For simplicity, we use 2 ** n sized SegTree.
        while m < n {
            m *= 2;
        }
        SegTree {
            n: m,
            dat: vec![init; 2 * m - 1],
            init: init,
            functor: f,
        }
    }

    // dat[k] = a;
    fn update(&mut self, k: usize, a: T) {
        let mut k = k;
        k += self.n - 1;
        self.dat[k] = a;
        while k > 0 {
            k = (k - 1) / 2;
            self.dat[k] = (self.functor)(self.dat[k * 2 + 1], self.dat[k * 2 + 2]);
        }
    }

    // [a, b)
    fn query(&self, a: usize, b: usize) -> T {
        self.query_inner(a, b, 0, 0, self.n)
    }

    fn query_inner(&self, a: usize, b: usize, k: usize, l: usize, r: usize) -> T {
        if r <= a || b <= l {
            return self.init;
        }
        if a <= l && r <= b {
            return self.dat[k];
        }

        let vl = self.query_inner(a, b, k * 2 + 1, l, (l + r) / 2);
        let vr = self.query_inner(a, b, k * 2 + 2, (l + r) / 2, r);
        (self.functor)(vl, vr)
    }
}
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