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QOJ
ID | 题目 | 提交者 | 结果 | 用时 | 内存 | 语言 | 文件大小 | 提交时间 | 测评时间 |
---|---|---|---|---|---|---|---|---|---|
#273185 | #7883. Takeout Delivering | ucup-team635# | ML | 0ms | 2100kb | Rust | 6.0kb | 2023-12-02 21:54:13 | 2023-12-02 21:54:15 |
Judging History
answer
use std::collections::*;
use std::io::Write;
type Map<K, V> = BTreeMap<K, V>;
type Set<T> = BTreeSet<T>;
type Deque<T> = VecDeque<T>;
fn main() {
input! {
n: usize,
m: usize,
e: [(usize1, usize1, i64); m],
}
let mut e = e;
for e in e.iter_mut() {
*e = (e.0.min(e.1), e.0.max(e.1), e.2);
}
e.sort_by_key(|e| e.2);
let mut g = vec![vec![]; n];
for &(a, b, c) in e.iter() {
g[a].push((a, b, c));
g[b].push((a, b, c));
}
let mut dp = vec![false; n];
let mut ep = vec![false; n];
dp[0] = true;
ep[n - 1] = true;
let mut dsu = DSU::new(n);
let mut tree = vec![vec![]; n];
let inf = std::i64::MAX / 3;
let mut val = inf;
let mut ans = inf;
for (a, b, c) in e {
if (a, b) == (0, n - 1) {
ans.chmin(c);
}
if let Some((p, ch)) = dsu.unite(a, b) {
tree[a].push((b, c));
tree[b].push((a, c));
if dp[p] != dp[ch] || ep[p] != ep[ch] {
for &r in [p, ch].iter() {
if (!dp[r] && dp[r ^ p ^ ch]) || (!ep[r] && ep[r ^ p ^ ch]) {
for &(a, b, w) in g[r].iter() {
let mut p = [dsu.root(0), dsu.root(n - 1)];
let mut q = [dsu.root(a), dsu.root(b)];
p.sort();
q.sort();
if p[0] != p[1] && p == q {
val.chmin(w);
}
}
}
}
}
dp[p] |= dp[ch];
ep[p] |= ep[ch];
let mut x = std::mem::take(&mut g[ch]);
g[p].append(&mut x);
}
ans.chmin(c + val);
}
/*
let mut dfs = vec![0];
let mut parent = vec![(n, 0); n];
parent[0].0 = 0;
while let Some(v) = dfs.pop() {
for &(u, w) in tree[v].iter() {
if parent[u].0 == n {
parent[u] = (v, w);
dfs.push(u);
}
}
}
let mut a = vec![];
let mut pos = n - 1;
while pos != 0 {
let p = parent[pos];
a.push(p.1);
pos = p.0;
}
a.sort();
ans.chmin(a.iter().rev().take(2).sum::<i64>());
*/
println!("{}", ans);
}
// ---------- begin input macro ----------
// reference: https://qiita.com/tanakh/items/0ba42c7ca36cd29d0ac8
#[macro_export]
macro_rules! input {
(source = $s:expr, $($r:tt)*) => {
let mut iter = $s.split_whitespace();
input_inner!{iter, $($r)*}
};
($($r:tt)*) => {
let s = {
use std::io::Read;
let mut s = String::new();
std::io::stdin().read_to_string(&mut s).unwrap();
s
};
let mut iter = s.split_whitespace();
input_inner!{iter, $($r)*}
};
}
#[macro_export]
macro_rules! input_inner {
($iter:expr) => {};
($iter:expr, ) => {};
($iter:expr, $var:ident : $t:tt $($r:tt)*) => {
let $var = read_value!($iter, $t);
input_inner!{$iter $($r)*}
};
}
#[macro_export]
macro_rules! read_value {
($iter:expr, ( $($t:tt),* )) => {
( $(read_value!($iter, $t)),* )
};
($iter:expr, [ $t:tt ; $len:expr ]) => {
(0..$len).map(|_| read_value!($iter, $t)).collect::<Vec<_>>()
};
($iter:expr, chars) => {
read_value!($iter, String).chars().collect::<Vec<char>>()
};
($iter:expr, bytes) => {
read_value!($iter, String).bytes().collect::<Vec<u8>>()
};
($iter:expr, usize1) => {
read_value!($iter, usize) - 1
};
($iter:expr, $t:ty) => {
$iter.next().unwrap().parse::<$t>().expect("Parse error")
};
}
// ---------- end input macro ----------
//---------- begin union_find ----------
pub struct DSU {
p: Vec<i32>,
}
impl DSU {
pub fn new(n: usize) -> DSU {
assert!(n < std::i32::MAX as usize);
DSU { p: vec![-1; n] }
}
pub fn init(&mut self) {
self.p.iter_mut().for_each(|p| *p = -1);
}
pub fn root(&self, mut x: usize) -> usize {
assert!(x < self.p.len());
while self.p[x] >= 0 {
x = self.p[x] as usize;
}
x
}
pub fn same(&self, x: usize, y: usize) -> bool {
assert!(x < self.p.len() && y < self.p.len());
self.root(x) == self.root(y)
}
pub fn unite(&mut self, x: usize, y: usize) -> Option<(usize, usize)> {
assert!(x < self.p.len() && y < self.p.len());
let mut x = self.root(x);
let mut y = self.root(y);
if x == y {
return None;
}
if self.p[x] > self.p[y] {
std::mem::swap(&mut x, &mut y);
}
self.p[x] += self.p[y];
self.p[y] = x as i32;
Some((x, y))
}
pub fn parent(&self, x: usize) -> Option<usize> {
assert!(x < self.p.len());
let p = self.p[x];
if p >= 0 {
Some(p as usize)
} else {
None
}
}
pub fn sum<F>(&self, mut x: usize, mut f: F) -> usize
where
F: FnMut(usize),
{
while let Some(p) = self.parent(x) {
f(x);
x = p;
}
x
}
pub fn size(&self, x: usize) -> usize {
assert!(x < self.p.len());
let r = self.root(x);
(-self.p[r]) as usize
}
}
//---------- end union_find ----------
// ---------- begin chmin, chmax ----------
pub trait ChangeMinMax {
fn chmin(&mut self, x: Self) -> bool;
fn chmax(&mut self, x: Self) -> bool;
}
impl<T: PartialOrd> ChangeMinMax for T {
fn chmin(&mut self, x: Self) -> bool {
*self > x && {
*self = x;
true
}
}
fn chmax(&mut self, x: Self) -> bool {
*self < x && {
*self = x;
true
}
}
}
// ---------- end chmin, chmax ----------
详细
Test #1:
score: 100
Accepted
time: 0ms
memory: 2100kb
input:
4 6 1 2 2 1 3 4 1 4 7 2 3 1 2 4 3 3 4 9
output:
5
result:
ok 1 number(s): "5"
Test #2:
score: -100
Memory Limit Exceeded
input:
300000 299999 80516 80517 597830404 110190 110191 82173886 218008 218009 954561262 250110 250111 942489774 66540 66541 156425292 34947 34948 239499776 273789 273790 453201232 84428 84429 439418398 98599 98600 326095035 55636 55637 355015760 158611 158612 684292473 43331 43332 43265001 171621 171622 ...
output:
1999991697