Submission #770850

#	Time	Username	Problem	Language	Result	Execution time	Memory
770850		marvinthang	Keys (IOI21_keys)	C++17	100 / 100	479 ms	55392 KiB

keys

/*************************************
*    author: marvinthang             *
*    created: 02.07.2023 10:24:06    *
*************************************/

#include <vector>
#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 << '}'; }

struct DisjointSet {
    
    int n, *lab = nullptr;

    DisjointSet(int _n = 0) {
        resize(_n);
    }

    void reset(void) {
        memset(lab, -1, (n + 1) * sizeof(int));
    }

    void resize(int _n) {
         if (lab != nullptr) delete[] lab;
         n = _n;
         lab = new int[n + 1];
         reset();
    }

    int find(int u) {
        assert(u <= n);
        return lab[u] < 0 ? u : lab[u] = find(lab[u]);
    }

    bool connected(int u, int v) { return find(u) == find(v); }
    bool isRoot(int u) { return lab[u] < 0; }
    int size(int u) { return -lab[find(u)]; }

    bool join(int u, int v) {
        if ((u = find(u)) == (v = find(v))) return false;
        if (lab[u] > lab[v]) swap(u, v);
        lab[u] += lab[v];
        lab[v] = u;
        return true;
    }

};

using DSU = DisjointSet;

// end of template

vector <int> find_reachable(vector <int> r, vector <int> u, vector <int> v, vector <int> c) {
	int n = r.size();
	int m = u.size();
	vector <vector <pair <int, int>>> adj(n);
	REP(i, m) {
		adj[u[i]].emplace_back(c[i], v[i]);
		adj[v[i]].emplace_back(c[i], u[i]);
	}
	DSU dsu(n);
	bool changed = true;
	vector <bool> done(n);
	int mi = n + 1;
	vector <int> res;
	while (changed) {
		changed = false;
		vector <bool> visited(n);
		vector <bool> keys(n);
		vector <vector <int>> kn(n);
		vector <int> his;
		auto bfs = [&] (int s) {
			for (int k: his) {
				keys[k] = false;
				kn[k].clear();
			}
			his.clear();
			vector <int> q;
			q.push_back(s);
			visited[s] = true;
			for (int i = 0; i < q.size(); ++i) {
				int u = q[i];
				if (!keys[r[u]]) {
					keys[r[u]] = true;
					his.push_back(r[u]);
					for (int v: kn[r[u]]) {
						int w = dsu.find(v);
						if (w != s) {
							visited[w] = true;
							dsu.lab[s] = w;
							return;
						}
						if (visited[v]) continue;
						visited[v] = true;
						q.push_back(v);
					}
					kn[r[u]].clear();
				}
				for (auto [c, v]: adj[u]) {
					if (keys[c]) {
						int w = dsu.find(v);
						if (w != s) {
							visited[w] = true;
							dsu.lab[s] = w;
							return;
						}
						if (visited[v]) continue;
						visited[v] = true;
						q.push_back(v);
					} else {
						if (kn[c].empty()) his.push_back(c);
						kn[c].push_back(v);
					}
				}
			}
			done[s] = true;
			if (mi > q.size()) {
				mi = q.size();
				res = q;
			} else if (mi == q.size()) res.insert(res.end(), ALL(q));
		};
		REP(i, n) if (!visited[i] && !done[i] && dsu.find(i) == i) {
			changed = true;
			bfs(i);
		}
	}
	vector <int> ans(n);
	for (int x: res) ans[x] = 1;
	return ans;
}

Compilation message (stderr)

keys.cpp: In lambda function:
keys.cpp:114:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  114 |    for (int i = 0; i < q.size(); ++i) {
      |                    ~~^~~~~~~~~~
keys.cpp:150:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  150 |    if (mi > q.size()) {
      |        ~~~^~~~~~~~~~
keys.cpp:153:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  153 |    } else if (mi == q.size()) res.insert(res.end(), ALL(q));
      |               ~~~^~~~~~~~~~~

• Subtask 1: 9 / 9
• Subtask 2: 11 / 11
• Subtask 3: 17 / 17
• Subtask 4: 30 / 30
• Subtask 5: 33 / 33