Submission #971805

#	Time	Username	Problem	Language	Result	Execution time	Memory
971805		marvinthang	Spring cleaning (CEOI20_cleaning)	C++17	100 / 100	109 ms	25172 KiB

cleaning

/*************************************
*    author: marvinthang             *
*    created: 29.04.2024 17:01:01    *
*************************************/

#include <bits/stdc++.h>

using namespace std;

#define                  fi  first
#define                  se  second
#define                left  ___left
#define               right  ___right
#define                TIME  (1.0 * clock() / CLOCKS_PER_SEC)
#define             MASK(i)  (1LL << (i))
#define           BIT(x, i)  ((x) >> (i) & 1)
#define  __builtin_popcount  __builtin_popcountll
#define              ALL(v)  (v).begin(), (v).end()
#define           REP(i, n)  for (int i = 0, _n = (n); i < _n; ++i)
#define          REPD(i, n)  for (int i = (n); i-- > 0; )
#define        FOR(i, a, b)  for (int i = (a), _b = (b); i < _b; ++i) 
#define       FORD(i, b, a)  for (int i = (b), _a = (a); --i >= _a; ) 
#define       FORE(i, a, b)  for (int i = (a), _b = (b); i <= _b; ++i) 
#define      FORDE(i, b, a)  for (int i = (b), _a = (a); i >= _a; --i) 
#define        scan_op(...)  istream & operator >> (istream &in, __VA_ARGS__ &u)
#define       print_op(...)  ostream & operator << (ostream &out, const __VA_ARGS__ &u)
#ifdef LOCAL
    #include "debug.h"
#else
    #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
    #define DB(...) 23
    #define db(...) 23
    #define debug(...) 23
#endif

template <class U, class V> scan_op(pair <U, V>)  { return in >> u.first >> u.second; }
template <class T> scan_op(vector <T>)  { for (size_t i = 0; i < u.size(); ++i) in >> u[i]; return in; }
template <class U, class V> print_op(pair <U, V>)  { return out << '(' << u.first << ", " << u.second << ')'; }
template <size_t i, class T> ostream & print_tuple_utils(ostream &out, const T &tup) { if constexpr(i == tuple_size<T>::value) return out << ")";  else return print_tuple_utils<i + 1, T>(out << (i ? ", " : "(") << get<i>(tup), tup); }
template <class ...U> print_op(tuple<U...>) { return print_tuple_utils<0, tuple<U...>>(out, u); }
template <class Con, class = decltype(begin(declval<Con>()))> typename enable_if <!is_same<Con, string>::value, ostream&>::type operator << (ostream &out, const Con &con) { out << '{'; for (__typeof(con.begin()) it = con.begin(); it != con.end(); ++it) out << (it == con.begin() ? "" : ", ") << *it; return out << '}'; }

// end of template

const int LOG = 17;

void process(void) {
	int n, q; cin >> n >> q;
	vector <vector <int>> adj(n);
	REP(i, n - 1) {
		int u, v; cin >> u >> v; --u; --v;
		adj[u].push_back(v);
		adj[v].push_back(u);
	}
	vector <int> parity(n), depth(n), tin(n), tout(n), pref_even(n);
	vector <array <int, LOG>> anc(n);
	vector <bool> is_leaf(n);
	auto dfs = [&] (auto &&dfs, int u, int par) -> void {
		static int t = 0;
		tin[u] = ++t;
		anc[u][0] = par;
		FOR(i, 1, LOG) anc[u][i] = anc[anc[u][i - 1]][i - 1];
		depth[u] = depth[par] + 1;
		is_leaf[u] = (int) adj[u].size() == 1;
		parity[u] = is_leaf[u];
		for (int v: adj[u]) if (v != par) {
			dfs(dfs, v, u);
			parity[u] ^= parity[v];
		}
		tout[u] = t;
	};
	dfs(dfs, 0, 0);
	auto dfs2 = [&] (auto &&dfs2, int u) -> void {
		pref_even[u] += parity[u];
		for (int v: adj[u]) if (v != anc[u][0]) {
			pref_even[v] = pref_even[u];
			dfs2(dfs2, v);
		}
	};
	dfs2(dfs2, 0);
	auto __lca = [&] (int u, int v) {
		if (depth[u] < depth[v]) swap(u, v);
		REPD(i, LOG) if (depth[anc[u][i]] >= depth[v]) u = anc[u][i];
		if (u == v) return u;
		REPD(i, LOG) if (anc[u][i] != anc[v][i]) {
			u = anc[u][i];
			v = anc[v][i];
		}
		return anc[u][0];
	};
	int init = n - 1;
	FOR(i, 1, n) init += !parity[i];
	vector <int> cur_parity(n);
	auto cmp = [&] (int u, int v) { return tin[u] < tin[v]; };
	REP(i, n) adj[i].clear();
	while (q--) {
		int d; cin >> d;
		vector <int> lst(d); cin >> lst;
		int res = init + d;
		for (int &u: lst) {
			--u;
			cur_parity[u] ^= 1;
		}
		sort(ALL(lst), cmp);
		lst.erase(unique(ALL(lst)), lst.end());
		for (int u: lst) if (is_leaf[u]) cur_parity[u] ^= 1;
		REP(i, (int) lst.size() - 1) lst.push_back(__lca(lst[i], lst[i + 1]));
		lst.push_back(0);
		sort(ALL(lst), cmp);
		lst.erase(unique(ALL(lst)), lst.end());
		stack <int> st;
		st.push(lst[0]);
		FOR(i, 1, lst.size()) {
			int u = lst[i];
			while (!st.empty() && (tin[u] < tin[st.top()] || tin[u] > tout[st.top()])) st.pop();
			adj[st.top()].push_back(u);
			st.push(u);
		}
		auto dfs = [&] (auto &&dfs, int u) -> void {
			for (int v: adj[u]) {
				dfs(dfs, v);
				if (cur_parity[v]) {
					res += 2 * (pref_even[v] - pref_even[u]) - (depth[v] - depth[u]);
				}
				cur_parity[u] ^= cur_parity[v];
			}
		};
		dfs(dfs, 0);
		cout << (cur_parity[0] ^ parity[0] ? -1 : res) << '\n';
		for (int u: lst) {
			cur_parity[u] = 0;
			adj[u].clear();
		}
	}
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("cleaning");
	// int t; cin >> t; while (t--)
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

Compilation message (stderr)

cleaning.cpp: In function 'int main()':
cleaning.cpp:30:61: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
cleaning.cpp:139:2: note: in expansion of macro 'file'
  139 |  file("cleaning");
      |  ^~~~
cleaning.cpp:30:94: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   30 |     #define file(name) if (fopen(name".inp", "r")) { freopen(name".inp", "r", stdin); freopen(name".out", "w", stdout); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
cleaning.cpp:139:2: note: in expansion of macro 'file'
  139 |  file("cleaning");
      |  ^~~~

• Subtask 1: 0 / 0
• Subtask 2: 9 / 9
• Subtask 3: 9 / 9
• Subtask 4: 16 / 16
• Subtask 5: 19 / 19
• Subtask 6: 17 / 17
• Subtask 7: 30 / 30