제출 #622524

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
622524		IWTIM	기지국 (IOI20_stations)	C++14	100 / 100	1070 ms	14944 KiB

stations

# include "stations.h"
# include <bits/stdc++.h>
using namespace std;
using namespace std;
using namespace std;
using ll = long long;
using db = long double; // or double, if TL is tight
using str = string; // yay python! 
 
// pairs
using pii = pair<int,int>;
using pl = pair<ll,ll>;
using pd = pair<db,db>;
#define mp make_pair
#define f first
#define s second
 
#define tcT template<class T
#define tcTU tcT, class U
// ^ lol this makes everything look weird but I'll try it
tcT> using V = vector<T>; 
tcT, size_t SZ> using AR = array<T,SZ>; 
using vi = V<int>;
using vb = V<bool>;
using vl = V<ll>;
using vd = V<db>;
using vs = V<str>;
using vpi = V<pii>;
using vpl = V<pl>;
using vpd = V<pd>;
 
// vectors
// oops size(x), rbegin(x), rend(x) need C++17
#define sz(x) int((x).size())
#define f first
#define s second
#define bg(x) begin(x)
#define all(x) bg(x), end(x)
#define rall(x) x.rbegin(), x.rend() 
#define sor(x) sort(all(x)) 
#define rsz resize
#define ins insert 
#define pb push_back
#define eb emplace_back
#define ft front()
#define bk back()
 
#define lb lower_bound
#define ub upper_bound
#define FOR(i,a,b) for (int i = (a); i < (b); ++i)
#define F0R(i,a) FOR(i,0,a)
#define ROF(i,a,b) for (int i = (b)-1; i >= (a); --i)
#define R0F(i,a) ROF(i,0,a)
#define rep(a) F0R(_,a)
#define each(a,x) for (auto& a: x)
const int MOD = 998244353;
const int MX = 2e5+5;
const ll BIG = 1e18; // not too close to LLONG_MAX
const db PI = acos((db)-1);
const int dx[4]{1,0,-1,0}, dy[4]{0,1,0,-1}; // for every grid problem!!
mt19937 rng((uint32_t)chrono::steady_clock::now().time_since_epoch().count()); 
template<class T> using pqg = priority_queue<T,vector<T>,greater<T>>;
struct DSU {
	vi e; void init(int N) { e = vi(N,-1); }
	int get(int x) { return e[x] < 0 ? x : e[x] = get(e[x]); } 
	bool sameSet(int a, int b) { return get(a) == get(b); }
	int size(int x) { return -e[get(x)]; }
	bool unite(int x, int y) { // union by size
		x = get(x), y = get(y); if (x == y) return 0;
		if (e[x] > e[y]) swap(x,y);
		e[x] += e[y]; e[y] = x; return 1;
	}
};
/*
inline namespace Helpers {
	//////////// is_iterable
	// https://stackoverflow.com/questions/13830158/check-if-a-variable-type-is-iterable
	// this gets used only when we can call begin() and end() on that type
	tcT, class = void> struct is_iterable : false_type {};
	tcT> struct is_iterable<T, void_t<decltype(begin(declval<T>())),
	                                  decltype(end(declval<T>()))
	                                 >
	                       > : true_type {};
	tcT> constexpr bool is_iterable_v = is_iterable<T>::value;
 
	//////////// is_readable
	tcT, class = void> struct is_readable : false_type {};
	tcT> struct is_readable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cin >> declval<T&>()), istream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_readable_v = is_readable<T>::value;
 
	//////////// is_printable
	// // https://nafe.es/posts/2020-02-29-is-printable/
	tcT, class = void> struct is_printable : false_type {};
	tcT> struct is_printable<T,
	        typename std::enable_if_t<
	            is_same_v<decltype(cout << declval<T>()), ostream&>
	        >
	    > : true_type {};
	tcT> constexpr bool is_printable_v = is_printable<T>::value;
}*/
const int N = 3e5 + 5;
int lv[N],tin,in[N],out[N];
vector <int> g[N];
void dfs(int a, int p) {
	lv[a] = (p == -1 ? 1 : (lv[p] + 1));
	tin++;
	in[a] = tin;
	for (int to : g[a]) {
		if (to == p) continue;
		dfs(to,a);
	}
	tin++;
	out[a] = tin;
}
vector<int> label(int n, int k, vector<int> u, vector<int> v) {
	vector <int> labels = vector <int> (n, 0);
	tin = 0;
	for (int i = 0; i < n; i++) {
		g[i].clear();
	}
	for (int i = 0; i < u.size(); i++) {
		int a = u[i];
		int b = v[i];
		g[a].pb(b);
		g[b].pb(a);
	}
	dfs(0, -1);
	vector <pii> vv;
	for (int i = 0; i < n; i++) {
		labels[i] = ((lv[i] % 2 == 1) ? in[i] : out[i]);
		vv.pb({labels[i], i});
	}
	sort(vv.begin(),vv.end());
	for (int i = 0; i < n; i++) {
		labels[vv[i].s] = i;
	}
	return labels;
}
int upper(int in, int out, int x) {
	return (in <= x && out >= x);
}
int find_next_station(int s, int t, std::vector<int> c) {
	if (c.size() == 1) {
		return c[0];
	}
	if (c[0] > s) {
		// lv[s] % 2 == 1  ( in[i] ) 
		// first child's IN = s + 1, OUT = c[0]
		if (upper(s + 1,c[0], t)) return c[0];
		for (int i = 1; i < (int)c.size() - 1; i++) {
			int in = c[i - 1] + 1;
			int out = c[i];
			if (upper(in,out, t)) return c[i];
		}
		return c.back();
 	}
 	if (c[0] < s) {
 		// lv[s] % 2 == 0 ( OUT[i] ) 
 		// last child's OUT = s - 1, in = c.back();
 		if (upper(c.back(), s - 1, t)) return c.back();
 		for (int i = (int)c.size() - 2; i >= 1; i--) {
 			int out = c[i + 1] - 1;
 			int in = c[i];
 			if (upper(in, out,t)) return c[i];
		 }
		 return c[0];
	 }
}

컴파일 시 표준 에러 (stderr) 메시지

stations.cpp: In function 'std::vector<int> label(int, int, std::vector<int>, std::vector<int>)':
stations.cpp:125:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  125 |  for (int i = 0; i < u.size(); i++) {
      |                  ~~^~~~~~~~~~
stations.cpp: In function 'int find_next_station(int, int, std::vector<int>)':
stations.cpp:172:1: warning: control reaches end of non-void function [-Wreturn-type]
  172 | }
      | ^

• Subtask 1: 5 / 5
• Subtask 2: 8 / 8
• Subtask 3: 16 / 16
• Subtask 4: 10 / 10
• Subtask 5: 61 / 61