結果
問題 | No.743 Segments on a Polygon |
ユーザー |
|
提出日時 | 2021-12-27 17:11:43 |
言語 | Rust (1.83.0 + proconio) |
結果 |
AC
|
実行時間 | 53 ms / 2,000 ms |
コード長 | 3,371 bytes |
コンパイル時間 | 11,977 ms |
コンパイル使用メモリ | 385,280 KB |
実行使用メモリ | 6,944 KB |
最終ジャッジ日時 | 2024-09-25 10:55:40 |
合計ジャッジ時間 | 13,481 ms |
ジャッジサーバーID (参考情報) |
judge5 / judge2 |
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ファイルパターン | 結果 |
---|---|
other | AC * 10 |
ソースコード
use std::cmp::*;// https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8macro_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, $t:ty) => ($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. 259 (http://yukicoder.me/submissions/100581)* AGC015-E (http://agc015.contest.atcoder.jp/submissions/1461001)* yukicoder No. 833 (https://yukicoder.me/submissions/703521)*/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 2SegTree {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) (note: half-inclusive)* http://proc-cpuinfo.fixstars.com/2017/07/optimize-segment-tree/ */#[allow(unused)]pub fn query(&self, mut a: usize, mut b: usize) -> I {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)}}fn main() {input! {n: usize, m: usize,ab: [(usize, usize); n],}let mut ab = ab;for v in &mut ab {if v.0 > v.1 {*v = (v.1, v.0);}}ab.sort();let mut st = SegTree::new(m, |a, b| a + b, 0i64);let mut tot = 0i64;for (a, b) in ab {let x = min(a, b);let y = max(a, b);tot += st.query(x, y);st.update(y, 1);}println!("{}", tot);}