제출 #883102

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
883102		marvinthang	조이터에서 친구를 만드는건 재밌어 (JOI20_joitter2)	C++17	100 / 100	319 ms	40548 KiB

joitter2

/*************************************
*    author: marvinthang             *
*    created: 04.12.2023 16:58:46    *
*************************************/

#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

void process(void) {
	int n, m; cin >> n >> m;
	vector <int> par(n, -1);
	function<int(int)> find = [&] (int u) {
		return par[u] < 0 ? u : par[u] = find(par[u]);
	};
	vector <set <int>> in(n);
	vector <set <pair <int, int>>> out(n);
	long long res = 0;
	REP(i, m) {
		int u, v; cin >> u >> v; --u; --v;
		vector <pair <int, int>> edges;
		edges.emplace_back(u, v);
		while (!edges.empty()) {
			auto [u, v] = edges.back();
			edges.pop_back();
			int rt_u = find(u); v = find(v);
			if (rt_u == v || in[v].count(u)) continue;
			auto it = out[v].lower_bound(pair{rt_u, 0});
			if (it != out[v].end() && it->fi == rt_u) {
				u = rt_u;
				if (par[u] > par[v]) swap(u, v);
				res += 2LL * par[u] * par[v];
				res += 1LL * in[u].size() * par[u] + 1LL * in[v].size() * par[v];
				for (auto it: out[v]) {
					if (it.fi == u) {
						in[u].erase(it.se);
						continue;
					}
					auto pt = out[it.fi].lower_bound(pair{u, 0});
					if (pt != out[it.fi].end() && pt->fi == u) {
						edges.emplace_back(it.se, it.fi);
						in[it.fi].erase(it.se);
						res += par[it.fi];
					} else out[u].insert(it);
				}
				out[v].clear();
				for (int w: in[v]) {
					int rt_w = find(w);
					if (rt_w == u) {
						out[u].erase(out[u].find(pair{v, w}));
						continue;
					}
					auto it = out[u].lower_bound(pair{rt_w, 0});
					if (it != out[u].end() && it->fi == rt_w) {
						edges.emplace_back(w, u);
						out[rt_w].erase(pair{v, w});
					} else {
						in[u].insert(w);
						out[rt_w].erase(pair{v, w});
						out[rt_w].insert(pair{u, w});
					}
				}
				in[v].clear();
				par[u] += par[v];
				par[v] = u;
				res -= 1LL * in[u].size() * par[u];
			} else {
				res -= par[v];
				out[rt_u].insert(pair{v, u});
				in[v].insert(u);
			}
		}
		cout << res << '\n';
	}
}

int main(void) {
	ios_base::sync_with_stdio(false); cin.tie(nullptr); // cout.tie(nullptr);
	file("JOI20_joitter2");
	// int t; cin >> t; while (t--)
	process();
	// cerr << "Time elapsed: " << TIME << " s.\n";
	return (0^0);
}

컴파일 시 표준 에러 (stderr) 메시지

joitter2.cpp: In function 'int main()':
joitter2.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); }
      |                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
joitter2.cpp:114:2: note: in expansion of macro 'file'
  114 |  file("JOI20_joitter2");
      |  ^~~~
joitter2.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); }
      |                                                                                       ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
joitter2.cpp:114:2: note: in expansion of macro 'file'
  114 |  file("JOI20_joitter2");
      |  ^~~~

• Subtask 1: 1 / 1
• Subtask 2: 16 / 16
• Subtask 3: 83 / 83