제출 #669318

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
669318		baojiaopisu	Inside information (BOI21_servers)	C++14	2.50 / 100	289 ms	86052 KiB

servers

#include<bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;
using ull = unsigned long long;

using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pld = pair<ld, ld>;

#define fi first
#define se second
#define left BAO
#define right ANH
#define pb push_back
#define pf push_front
#define mp make_pair
#define ins insert
#define btpc __builtin_popcount
#define btclz __builtin_clz

#define sz(x) (int)(x.size());
#define all(x) x.begin(), x.end()
#define debug(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int d4x[4] = {1, 0, -1, 0}; int d4y[4] = {0, 1, 0, -1};
int d8x[8] = {0, 1, 1, 1, 0, -1, -1, -1};
int d8y[8] = {1, 1, 0, -1, -1, -1, 0, 1};

template<class X, class Y>
    bool minimize(X &x, const Y &y) {
        if (x > y)
        {
            x = y;
            return true;
        }
        return false;
    }
template<class X, class Y>
    bool maximize(X &x, const Y &y) {
        if (x < y)
        {
            x = y;
            return true;
        }
        return false;
    }

const int MOD = 1e9 + 7; //998244353

template<class X, class Y>
	void add(X &x, const Y &y) {
		x = (x + y);
		if(x >= MOD) x -= MOD;
	}

template<class X, class Y> 
	void sub(X &x, const Y &y) {
		x = (x - y);
		if(x < 0) x += MOD;
	}

/* Author : Le Ngoc Bao Anh, 12A5, LQD High School for Gifted Student*/

const ll INF = 1e9;
const int N = 2e5 + 10;
const int LOG = 17;

vector<pii> g[N];
pii par[N];
int depth[N], in[N], de[N], l[N], r[N], sz[N];
int cpar[N], cdepth[N];
int res[N];
bool visited[N];
int f[N][LOG + 2], cnt[N];
vector<int> upd[N];
int Time = 0;

template <class T> struct FenwickTree {
	int n;
	vector<T> bit;

	FenwickTree(int _n = 0) {
		n = _n;
		bit.resize(n + 5);
		for(int i = 1; i <= n; i++) bit[i] = 0;
	}

	void update(int pos, T x) {
		for(int i = pos; i <= n; i += i & (-i)) bit[i] += x;
	}

	T get(int pos) {
		T ans = 0;
		for(int i = pos; i > 0; i -= i & (-i)) ans += bit[i];
		return ans;
	}
};
FenwickTree<int> BIT;

struct Queries {
	int type, u, v, id;
};
vector<Queries> queries;

struct Edges {
	int u, v, w;
};
vector<Edges> ed;

struct P {
	int u, id, idq;
};
vector<P> path;

void dfs(int u) {
	l[u] = ++Time;
	for(auto nxt : g[u]) {
		int v = nxt.fi;
		int w = nxt.se;

		if(v != par[u].fi) {
			par[v] = mp(u, w);
			depth[v] = depth[u] + 1;
			if(u == 1) {
				in[v] = de[v] = u;
			} else {
				in[v] = (w < par[u].se ? in[u] : u);
				de[v] = (w > par[u].se ? de[u] : u);
			}
			dfs(v);
		}
	}
	r[u] = Time;
}

int find_lca(int u, int v) {
	if(depth[u] < depth[v]) swap(u, v);
	for(int i = LOG; i >= 0; i--) {
		if(depth[u] - (1 << i) >= depth[v]) u = f[u][i];
	}

	if(u == v) return u;

	for(int i = LOG; i >= 0; i--) {
		if(f[u][i] != f[v][i]) {
			u = f[u][i];
			v = f[v][i];
		}
	}

	return f[u][0];
}

int find_par(int u, int d) {
	for(int i = LOG; i >= 0; i--) {
		if(depth[u] - (1 << i) >= d) u = f[u][i];
	}

	return u;
}

bool can_go(int u, int v, int id) {
	int p = find_lca(u, v);

	if(u == v) return true;

	bool ok = (depth[in[u]] <= depth[p] && depth[de[v]] <= depth[p]);

	int prv;
	if(v == p) {
		prv = find_par(u, depth[p] + 1);
		ok &= (par[prv].se <= id);
	} else ok &= (par[v].se <= id);

	if(u != p && v != p) {
		u = find_par(u, depth[p] + 1);
		v = find_par(v, depth[p] + 1);
		ok &= (par[u].se <= par[v].se);
	}

	return ok;
}

void dfs_sz(int u, int par) {
	sz[u] = 1;
	for(auto nxt : g[u]) {
		int v = nxt.fi;
		int w = nxt.se;
		if(!visited[v] && v != par) {
			dfs_sz(v, u);
			sz[u] += sz[v];
		}
	}
}

int centroid(int u, int par, int n) {
	for(auto nxt : g[u]) {
		int v = nxt.fi;
		if(v != par && !visited[v] && sz[v] * 2 > n) return centroid(v, u, n);
	}

	return u;
}

int build_centroid(int u) {
	dfs_sz(u, 0);
	u = centroid(u, 0, sz[u]);
	visited[u] = true;

	for(auto nxt : g[u]) {
		int v = nxt.fi;
		if(!visited[v]) {
			int x = build_centroid(v);
			cdepth[x] = cdepth[u] + 1;
			cpar[x] = u;
		}
	}

	return u;
}

int first_edge(int u, int v) {
	if(u == v) return INF;
	if(l[u] <= l[v] && r[v] <= r[u]) {
		int p = find_par(v, depth[u] + 1);
		return par[p].se;
	}

	return par[u].se;
}

int last_edge(int u, int v) {
	if(u == v) return 0;
	if(l[v] <= l[u] && r[u] <= r[v]) {
		int p = find_par(u, depth[v] + 1);
		return par[p].se;
	}

	return par[v].se;
}

void BaoJiaoPisu() {
	int n, q; cin >> n >> q; q += n - 1;

	for(int i = 1; i <= q; i++) {
		char c; cin >> c;
		if(c == 'S') {
			int u, v; cin >> u >> v;
			g[u].pb(mp(v, i));
			g[v].pb(mp(u, i));
			ed.pb({u, v, i});
		}

		if(c == 'Q') {
			int a, b; cin >> a >> b;
			queries.pb({0, a, b, i});
		}

		if(c == 'C') {
			int a; cin >> a;
			queries.pb({1, a, 0, i});
		}
	}

	depth[1] = 1;
	dfs(1);

	for(int i = 1; i <= n; i++) f[i][0] = par[i].fi;

	for(int j = 1; j <= LOG; j++) {
		for(int i = 1; i <= n; i++) {
			if(depth[i] <= (1 << j)) continue;
			int u = f[i][j - 1];
			f[i][j] = f[u][j - 1];
		}
	}

	de[1] = in[1] = 1;

	build_centroid(1);

	for(int i = 0; i < queries.size(); i++) {
		if(!queries[i].type) {
			int id = queries[i].id;
			int u = queries[i].v, v = queries[i].u;
			res[i] = can_go(u, v, id);
		} else {
			int id = queries[i].id;
			int u = queries[i].u;
			int v = u;

			while(v) {
				if(can_go(u, v, id) && last_edge(u, v) <= id) path.pb({v, last_edge(u, v) + 1, i});

				v = cpar[v];
			}
		}
	}

	sort(all(path), [&](P x, P y) {
		return x.id > y.id;
	});

	for(int i = 1; i <= n; i++) cnt[i]++;

	for(int i = 1; i <= n; i++) {
		int u = i, v = cpar[i];
		while(v) {
			if(can_go(v, u, INF)) {
				upd[first_edge(v, u)].pb(v);
			}
			v = cpar[v];
		}
	}

	int iter = ed.size() - 1;
	for(int i = 0; i < path.size(); i++) {
		int id = path[i].id;
		while(iter >= 0 && ed[iter].w >= id) {
			int w = ed[iter].w;
			for(auto u : upd[w]) ++cnt[u];
			iter--;
		}

		int idq = path[i].idq;
		int u = path[i].u;
		res[idq] += cnt[u];
	}

	for(int i = 0; i < queries.size(); i++) {
		if(!queries[i].type) {
			cout << (res[i] ? "yes" : "no") << '\n';
		} else cout << res[i] << '\n';
	}
}

int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

    int tc = 1, ddd = 0;
    // cin >> tc;
    while(tc--) {
        //ddd++;
        //cout << "Case #" << ddd << ": ";
        BaoJiaoPisu();
    }
}

컴파일 시 표준 에러 (stderr) 메시지

servers.cpp: In function 'void dfs_sz(int, int)':
servers.cpp:193:7: warning: unused variable 'w' [-Wunused-variable]
  193 |   int w = nxt.se;
      |       ^
servers.cpp: In function 'void BaoJiaoPisu()':
servers.cpp:287:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Queries>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  287 |  for(int i = 0; i < queries.size(); i++) {
      |                 ~~^~~~~~~~~~~~~~~~
servers.cpp:322:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<P>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  322 |  for(int i = 0; i < path.size(); i++) {
      |                 ~~^~~~~~~~~~~~~
servers.cpp:335:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<Queries>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  335 |  for(int i = 0; i < queries.size(); i++) {
      |                 ~~^~~~~~~~~~~~~~~~
servers.cpp: In function 'int main()':
servers.cpp:346:17: warning: unused variable 'ddd' [-Wunused-variable]
  346 |     int tc = 1, ddd = 0;
      |                 ^~~

• Subtask 1: 2.5 / 2.5
• Subtask 2: 0 / 2.5
• Subtask 3: 0 / 2.5
• Subtask 4: 0 / 2.5
• Subtask 5: 0 / 5
• Subtask 6: 0 / 5
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 12.5
• Subtask 10: 0 / 12.5
• Subtask 11: 0 / 17.5
• Subtask 12: 0 / 17.5