結果
| 問題 |
No.1874 Minimum of Sum of Rectangles
|
| コンテスト | |
| ユーザー |
 koba-e964
|
| 提出日時 | 2025-08-18 19:03:23 |
| 言語 | Rust (1.83.0 + proconio) |
| 結果 |
AC
|
| 実行時間 | 189 ms / 3,000 ms |
| コード長 | 7,147 bytes |
| コンパイル時間 | 12,976 ms |
| コンパイル使用メモリ | 399,652 KB |
| 実行使用メモリ | 69,152 KB |
| 最終ジャッジ日時 | 2025-08-18 19:03:44 |
| 合計ジャッジ時間 | 18,234 ms |
|
ジャッジサーバーID （参考情報） |
judge2 / judge1 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 39 |
コンパイルメッセージ
warning: unused import: `BufWriter`
--> src/main.rs:1:22
|
1 | use std::io::{Write, BufWriter};
| ^^^^^^^^^
|
= note: `#[warn(unused_imports)]` on by default
warning: unused import: `Write`
--> src/main.rs:1:15
|
1 | use std::io::{Write, BufWriter};
| ^^^^^
ソースコード
use std::io::{Write, BufWriter};
// 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),* )) => { ($(read_value!($next, $t)),*) };
($next:expr, [ $t:tt ; $len:expr ]) => {
(0..$len).map(|_| read_value!($next, $t)).collect::<Vec<_>>()
};
($next:expr, usize1) => (read_value!($next, usize) - 1);
($next:expr, $t:ty) => ($next().parse::<$t>().expect("Parse error"));
}
// Segment Tree. This data structure is useful for fast folding on intervals of an array
// whose elements are elements of monoid I. Note that constructing this tree requires the identity
// element of I and the operation of I.
// Verified by: yukicoder No. 2220 (https://yukicoder.me/submissions/841554)
struct SegTree<I, BiOp> {
n: usize,
orign: usize,
dat: Vec<I>,
op: BiOp,
e: I,
}
impl<I, BiOp> SegTree<I, BiOp>
where BiOp: Fn(I, I) -> I,
I: Copy {
pub fn new(n_: usize, op: BiOp, e: I) -> Self {
let mut n = 1;
while n < n_ { n *= 2; } // n is a power of 2
SegTree {n: n, orign: n_, dat: vec![e; 2 * n - 1], op: op, e: e}
}
// ary[k] <- v
pub fn update(&mut self, idx: usize, v: I) {
debug_assert!(idx < self.orign);
let mut k = idx + self.n - 1;
self.dat[k] = v;
while k > 0 {
k = (k - 1) / 2;
self.dat[k] = (self.op)(self.dat[2 * k + 1], self.dat[2 * k + 2]);
}
}
// [a, b) (half-inclusive)
// http://proc-cpuinfo.fixstars.com/2017/07/optimize-segment-tree/
#[allow(unused)]
pub fn query(&self, rng: std::ops::Range<usize>) -> I {
let (mut a, mut b) = (rng.start, rng.end);
debug_assert!(a <= b);
debug_assert!(b <= self.orign);
let mut left = self.e;
let mut right = self.e;
a += self.n - 1;
b += self.n - 1;
while a < b {
if (a & 1) == 0 {
left = (self.op)(left, self.dat[a]);
}
if (b & 1) == 0 {
right = (self.op)(self.dat[b - 1], right);
}
a = a / 2;
b = (b - 1) / 2;
}
(self.op)(left, right)
}
}
// Depends on: datastr/SegTree.rs
// Verified by: yukicoder No. 2220 (https://yukicoder.me/submissions/841554)
impl<I, BiOp> SegTree<I, BiOp>
where BiOp: Fn(I, I) -> I,
I: Copy {
// Port from https://github.com/atcoder/ac-library/blob/master/atcoder/segtree.hpp
#[allow(unused)]
fn max_right<F: Fn(I) -> bool>(
&self, rng: std::ops::RangeFrom<usize>, f: &F,
) -> usize {
let mut l = rng.start;
assert!(f(self.e));
if l == self.orign {
return self.orign;
}
l += self.n - 1;
let mut sm = self.e;
loop {
while l % 2 == 1 {
l = (l - 1) / 2;
}
if !f((self.op)(sm, self.dat[l])) {
while l < self.n - 1 {
l = 2 * l + 1;
let val = (self.op)(sm, self.dat[l]);
if f(val) {
sm = val;
l += 1;
}
}
return std::cmp::min(self.orign, l + 1 - self.n);
}
sm = (self.op)(sm, self.dat[l]);
l += 1;
if (l + 1).is_power_of_two() { break; }
}
self.orign
}
// Port from https://github.com/atcoder/ac-library/blob/master/atcoder/segtree.hpp
#[allow(unused)]
fn min_left<F: Fn(I) -> bool>(
&self, rng: std::ops::RangeTo<usize>, f: &F,
) -> usize {
let mut r = rng.end;
if !f(self.e) {
return r + 1;
}
if r == 0 {
return 0;
}
r += self.n - 1;
let mut sm = self.e;
loop {
r -= 1;
while r > 0 && r % 2 == 0 {
r = (r - 1) / 2;
}
if !f((self.op)(self.dat[r], sm)) {
while r < self.n - 1 {
r = 2 * r + 2;
let val = (self.op)(self.dat[r], sm);
if f(val) {
sm = val;
r -= 1;
}
}
return r + 2 - self.n;
}
sm = (self.op)(self.dat[r], sm);
if (r + 1).is_power_of_two() { break; }
}
0
}
}
// https://yukicoder.me/problems/no/1874 (4)
// Q として妥当なのは P の x 座標と y 座標なので、 N^2 通りしかない。
// y 座標を固定して、 x 座標を二分探索することで O(N log N) で解ける。
// 途中で \sum |A_i - Y| の計算が必要になるので、平面走査する。
// -> 同じ x 座標に複数の点が存在し得るのを見逃していた。
// Tags: plane-scanning
// Similar-problems: https://yukicoder.me/problems/no/3078
fn main() {
input! {
n: usize,
xy: [(usize, usize); n],
}
const W: usize = 1_000_001;
let mut ev = vec![];
for i in 0..n {
let (x, y) = xy[i];
ev.push((y, x));
}
ev.sort();
let mut st = SegTree::new(W, |x, y| (x.0 + y.0, x.1 + y.1), (0i64, 0i64));
let mut st_sum = SegTree::new(W, |x, y| (x.0 + y.0, x.1 + y.1), (0i64, 0i64));
for i in 0..n {
let (x, y) = xy[i];
let old = st.query(x..x + 1);
st.update(x, (old.0 + y as i64, old.1 - 1));
let old_sum = st_sum.query(x..x + 1);
st_sum.update(x, (old_sum.0 + x as i64 * y as i64, old_sum.1 - x as i64));
}
let mut ans = 1i64 << 60;
for (y, x) in ev {
let (sum, cnt) = st.query(0..W);
let all = sum + cnt * y as i64;
let r = st.max_right(0.., &|(sum, cnt)| 2 * (sum + cnt * y as i64) <= all);
let (sum, cnt) = st.query(0..r);
let (sum_s, cnt_s) = st_sum.query(0..r);
let half = -(sum_s + cnt_s * y as i64) + (sum + cnt * y as i64) * r as i64;
let (sum, cnt) = st.query(r..W);
let (sum_s, cnt_s) = st_sum.query(r..W);
let half2 = (sum_s + cnt_s * y as i64) - (sum + cnt * y as i64) * r as i64;
ans = ans.min(half + half2);
let old = st.query(x..x + 1);
st.update(x, (old.0 - 2 * y as i64, old.1 + 2));
let old_sum = st_sum.query(x..x + 1);
st_sum.update(x, (old_sum.0 - 2 * x as i64 * y as i64, old_sum.1 + 2 * x as i64));
}
println!("{ans}");
}