Submission #776198

#	Time	Username	Problem	Language	Result	Execution time	Memory
776198		marvinthang	Jail (JOI22_jail)	C++17	100 / 100	2025 ms	505036 KiB

jail

/*************************************
*    author: marvinthang             *
*    created: 07.07.2023 17:53:07    *
*************************************/

#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--; )
#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 << '}'; }
template <class A, class B> bool minimize(A &a, B b)  { if (a > b) { a = b; return true; } return false; }
template <class A, class B> bool maximize(A &a, B b)  { if (a < b) { a = b; return true; } return false; }

// end of template

const int MAX = 1.2e5 + 5;
const int LOG = 20;

int N, M;
vector <int> tree_adj[MAX];
int depth[MAX], anc[MAX][LOG];

void init(void) {
	cin >> N;
	FORE(i, 1, N) tree_adj[i].clear();
	FOR(i, 1, N) {
		int u, v; cin >> u >> v;
		tree_adj[u].push_back(v);
		tree_adj[v].push_back(u);
	}
	cin >> M;
}

void dfs(int u) {
	depth[u] = depth[anc[u][0]] + 1;
	FOR(i, 1, LOG) anc[u][i] = anc[anc[u][i - 1]][i - 1];
	for (int v: tree_adj[u]) if (v != anc[u][0]) {
		anc[v][0] = u;
		dfs(v);
	}
}

int in[MAX][LOG], out[MAX][LOG];
vector <int> adj[MAX * LOG * 2];
int low[MAX * LOG * 2], num[MAX * LOG * 2];
bool imp[MAX * LOG * 2];

int getParent(int u, int h) {
	REP(i, LOG) if (BIT(h, i)) u = anc[u][i];
	return u;
}

int __lca(int u, int v) {
	if (depth[u] < depth[v]) swap(u, v);
	u = getParent(u, depth[u] - depth[v]);
	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];
}

stack <int> st;
int timeDfs;

bool dfs2(int u) {
	st.push(u);
	low[u] = num[u] = ++timeDfs;
	for (int v: adj[u]) {
		if (!num[v]) {
			if (dfs2(v)) return true;
			minimize(low[u], low[v]);
		} else minimize(low[u], num[v]);
	}
	if (low[u] == num[u]) {
		int v, cnt = 0;
		do {
			v = st.top(); st.pop();
			cnt += imp[v];
			low[v] = num[v] = 1e9;
		} while (v != u);
		if (cnt > 1) return true;
	}
	return false;
}

void process(void) {
	dfs(1);
	int cnt = 0;
	REP(j, LOG) FORE(i, 1, N) if (depth[i] >= MASK(j)) {
		low[cnt] = num[cnt] = 0;
		adj[cnt].clear();
		imp[cnt] = !j;
		in[i][j] = cnt++;

		low[cnt] = num[cnt] = 0;
		adj[cnt].clear();
		imp[cnt] = false;
		out[i][j] = cnt++;

		if (j) {
			int p = anc[i][j - 1];
			adj[in[i][j - 1]].push_back(in[i][j]);
			adj[in[p][j - 1]].push_back(in[i][j]);
			adj[out[i][j]].push_back(out[i][j - 1]);
			adj[out[i][j]].push_back(out[p][j - 1]);
		}
	}
	while (M--) {
		int u, v; cin >> u >> v;
		adj[in[u][0]].push_back(out[v][0]);
		adj[out[v][0]].push_back(in[u][0]);

		int lca = __lca(u, v);
		auto addEdge = [&] (int a, int h) {
			adj[in[a][h]].push_back(in[u][0]);
			adj[out[v][0]].push_back(out[a][h]);
		};
		int h = __lg(depth[u] - depth[lca] + 1);
		addEdge(u, h);
		addEdge(getParent(u, depth[u] - depth[lca] + 1 - MASK(h)), h);
		if (v != lca) {
			h = __lg(depth[v] - depth[lca]);
			addEdge(v, h);
			addEdge(getParent(v, depth[v] - depth[lca] - MASK(h)), h);
		}
	}
	while (!st.empty()) st.pop();
	timeDfs = 0;
	REP(i, cnt) if (!num[i] && dfs2(i)) return void(cout << "No\n");
	cout << "Yes\n";
}

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

Compilation message (stderr)

jail.cpp: In function 'int main()':
jail.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
jail.cpp:168:2: note: in expansion of macro 'file'
  168 |  file("jail");
      |  ^~~~
jail.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
jail.cpp:168:2: note: in expansion of macro 'file'
  168 |  file("jail");
      |  ^~~~

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 16 / 16
• Subtask 4: 28 / 28
• Subtask 5: 12 / 12
• Subtask 6: 11 / 11
• Subtask 7: 23 / 23