oj.uz

Submission #934234

# Submission time Handle Problem Language Result Execution time Memory
934234 2024-02-27T03:09:39 Z Joshua_Andersson Inside information (BOI21_servers) C++14
50 / 100
 3500 ms 115064 KB 
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
//#define int ll
const int inf = int(1e9);

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef pair<int, int> p2;

#define rep(i, high) for (int i = 0; i < high; i++)
#define repp(i, low, high) for (int i = low; i < high; i++)
#define repe(i, container) for (auto& i : container)
#define sz(container) ((int)container.size())
#define all(x) begin(x),end(x)
#define ceildiv(x,y) ((x + y - 1) / (y))

inline void fast() { ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); }

#define _LOCAL _DEBUG
#if _LOCAL
#define assert(x) if (!(x)) __debugbreak()
#endif

const int maxn = int(1.5e5);
int tin[maxn];
int tout[maxn];
int timer = 0;
int up[maxn][18];
bool upincreasing[maxn][18];
bool updecreasing[maxn][18];
int upmax[maxn][18];
int upmin[maxn][18];
int upv[maxn];
int depth[maxn];

void dfs(int u, int p, int p1, int _p2, vector<vector<p2>>& edges)
{
	depth[u] = depth[p] + 1;
	tin[u] = timer++;
	up[u][0] = p;
	upmax[u][0] = upv[u];
	upmin[u][0] = upv[u];
	upincreasing[u][0] = upmax[u][0] < upmax[p][0] || p==0 || u==0;
	updecreasing[u][0] = upmax[u][0] > upmax[p][0] || p==0 || u==0;
	repp(d,1,18)
	{
		int mid = up[u][d - 1];
		up[u][d] = up[mid][d - 1];
		upmax[u][d] = max(upmax[u][d - 1], upmax[mid][d - 1]);
		upmin[u][d] = min(upmin[u][d - 1], upmin[mid][d - 1]);
		upincreasing[u][d] = upincreasing[u][d - 1] && upincreasing[mid][d - 1] && (upmax[mid][0] < upmax[up[mid][0]][0] || up[mid][0] ==0||mid==0);
		updecreasing[u][d] = updecreasing[u][d - 1] && updecreasing[mid][d - 1] && (upmax[mid][0] > upmax[up[mid][0]][0] || up[mid][0] ==0||mid==0);
	}
	

	repe(e, edges[u]) if (e.first != p)
	{
		upv[e.first] = e.second;
		dfs(e.first, u, p1, _p2, edges);
	}

	tout[u] = timer++;
}

bool isancestor(int a, int b)
{
	return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int pathmax(int a, int b)
{
	if (isancestor(a, b)) return -1;
	int ret = -1;
	for (int d = 17; d >= 0; d--)
	{
		if (!isancestor(up[a][d], b))
		{
			ret = max(ret, upmax[a][d]);
			a = up[a][d];
		}
	}
	return max(ret, upmax[a][0]);
}

int pathmin(int a, int b)
{
	if (isancestor(a, b)) return inf;
	int ret = inf;
	for (int d = 17; d >= 0; d--)
	{
		if (!isancestor(up[a][d], b))
		{
			ret = min(ret, upmin[a][d]);
			a = up[a][d];
		}
	}
	return min(ret, upmin[a][0]);
}

struct Centroid
{
	int n;
	vvi edges;
	vi vis;
	vi par;
	vi size;

	Centroid() {}
	Centroid(vvi& edges) : edges(edges), n(edges.size()), vis(n), par(n), size(n)
	{
		init_centroid(0, -1);
	}

	int find_centroid(int u, int p, int n)
	{
		repe(e, edges[u])
		{
			if (e == p) continue;
			if (!vis[e] && size[e] > n / 2) return find_centroid(e, u, n);
		}
		return u;
	}

	int find_size(int u, int p)
	{
		if (vis[u]) return 0;
		size[u] = 1;

		repe(e, edges[u])
		{
			if (e == p) continue;
			size[u] += find_size(e, u);
		}
		return size[u];
	}

	void init_centroid(int u, int p)
	{
		find_size(u, u);

		int c = find_centroid(u, u, size[u]);
		vis[c] = 1;
		par[c] = p;

		repe(e, edges[c])
		{
			if (!vis[e]) init_centroid(e, c);
		}
	}
};

int cdepth[maxn];
void d(int u, int p, vvi& adj)
{
	cdepth[u] = cdepth[p] + 1;
	repe(e, adj[u]) if (e != p) d(e, u, adj);
}

signed main()
{
	fast();

	//ifstream in("C:\\Users\\Matis\\desktop\\comp_prog\\x64\\debug\\in.txt");
	//cin.rdbuf(in.rdbuf());

	int n, q;
	cin >> n >> q;

	vvi queries;
	int t = 0;
	vector<vector<p2>> edges(n);
	vector<p2> edgelist;
	vvi e(n);
	rep(i, n + q - 1)
	{
		char c;
		cin >> c;
		if (c=='S')
		{
			int a, b;
			cin >> a >> b;
			a--; b--;
			edgelist.push_back(p2(a, b));
			edges[a].push_back(p2(b, t));
			edges[b].push_back(p2(a, t));
			e[a].push_back(b);
			e[b].push_back(a);
			t++;
		}
		else if (c=='Q')
		{
			int a, b;
			cin >> a >> b;
			a--; b--;
			queries.push_back({ 0, b, a, t-1 });
		}
		else
		{
			int c;
			cin >> c;
			c--;
			queries.push_back({ 1, c, -1, t-1 });
		}
	}
	depth[0] = 0;
	dfs(0, 0, -1, -1, edges);
	Centroid cent(e);

	auto getmax = [&](int a, int b)
	{
		return max(pathmax(a, b), pathmax(b, a));
	};
	
	auto getmin = [&](int a, int b)
	{
		return min(pathmin(a, b), pathmin(b, a));
	};

	auto pathgood = [&](int a, int b, int t)
	{
		if (getmax(a, b) > t) return false;
		// all edges <= t
		// from b->lca increasing
		// from a->lca decreasing
		bool good = 1;
		int u = b;
		int prev = inf;
		for (int d = 17; d >= 0; d--)
		{
			if (!isancestor(up[u][d],a))
			{
				good &= updecreasing[u][d];
				u = up[u][d];
			}
		}
		if (!isancestor(u,a))
		{
			prev = upmax[u][0];
		}
		

		u = a;
		int v = -1;
		for (int d = 17; d >= 0; d--)
		{
			if (!isancestor(up[u][d], b))
			{
				good &= upincreasing[u][d];
				u = up[u][d];
			}
		}
		if (!isancestor(u, b))
		{
			v = upmax[u][0];
		}

		return good && (v < prev);
	};

	vector<map<int,int>> children(n);
	vi sum(n);
	vvi blocked(n);
	rep(i, n)blocked[i].push_back(inf);
	vi parenton(n);
	vi centroidpar = cent.par;
	vvi centroidadj(n);
	rep(i, n)
	{
		if (centroidpar[i] == -1) continue;
		centroidadj[i].push_back(centroidpar[i]);
		centroidadj[centroidpar[i]].push_back(i);
	}
	Centroid c2(e);
	c2.find_size(0, 0);
	int center = c2.find_centroid(0, 0, c2.size[0]);
	d(center, center, centroidadj);

	auto enable = [&](int ind)
	{
		int u = cdepth[edgelist[ind].first] > cdepth[edgelist[ind].second] ? edgelist[ind].first : edgelist[ind].second;
		int s = u;
		while (true)
		{
			if (!pathgood(s,u,ind)) break;
			if (centroidpar[u] == -1) break;
			int pe = getmin(u, centroidpar[u]);
			repe(c, blocked[u])
			{
				if (c>pe)
				{
					children[centroidpar[u]][pe]++;
					blocked[centroidpar[u]].push_back(pe);
				}
			}
			blocked[u] = vi();
			u = centroidpar[u];
		}
	};

	int timer = 0;
	repe(q, queries)
	{
		int type=q[0], a=q[1], b=q[2], t=q[3];
		
		if (type==0)
		{
			cout << (pathgood(a, b, t) ? "yes" : "no") << "\n";
		}
		else
		{
			
			while (timer<=t)
			{
				enable(timer++);
			}
			
			int ans = 0;
			repe(c, children[a]) ans += c.second;
			int u=a;
			
			while (u!=0)
			{
				u = centroidpar[u];
				if (!pathgood(a, u, t)) break;
				ans++;
				int prev = getmin(a, u);
				repe(c, children[u]) if (c.first > prev) ans += c.second;
				if (u == 0)
				{
					break;
				}
			}

			cout << ans+1 << "\n";
		}
	}

	return 0;
}

Compilation message

servers.cpp: In constructor 'Centroid::Centroid(vvi&)':
servers.cpp:105:6: warning: 'Centroid::edges' will be initialized after [-Wreorder]
  105 |  vvi edges;
      |      ^~~~~
servers.cpp:104:6: warning:   'int Centroid::n' [-Wreorder]
  104 |  int n;
      |      ^
servers.cpp:111:2: warning:   when initialized here [-Wreorder]
  111 |  Centroid(vvi& edges) : edges(edges), n(edges.size()), vis(n), par(n), size(n)
      |  ^~~~~~~~

Subtask #1
2.5 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 34 ms 17664 KB Output is correct
2 Correct 43 ms 21252 KB Output is correct
3 Correct 49 ms 21756 KB Output is correct
4 Correct 52 ms 21496 KB Output is correct
5 Correct 60 ms 22016 KB Output is correct
6 Correct 42 ms 21500 KB Output is correct

Subtask #2
0 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 34 ms 17664 KB Output is correct
2 Correct 43 ms 21252 KB Output is correct
3 Correct 49 ms 21756 KB Output is correct
4 Correct 52 ms 21496 KB Output is correct
5 Correct 60 ms 22016 KB Output is correct
6 Correct 42 ms 21500 KB Output is correct
7 Incorrect 41 ms 17676 KB Extra information in the output file
8 Halted 0 ms 0 KB -

Subtask #3
2.5 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 36 ms 17684 KB Output is correct
2 Correct 209 ms 98592 KB Output is correct
3 Correct 207 ms 98540 KB Output is correct

Subtask #4
0 / 2.5

# Verdict Execution time Memory Grader output
1 Correct 36 ms 17684 KB Output is correct
2 Correct 209 ms 98592 KB Output is correct
3 Correct 207 ms 98540 KB Output is correct
4 Correct 31 ms 17696 KB Output is correct
5 Execution timed out 3540 ms 101112 KB Time limit exceeded
6 Halted 0 ms 0 KB -

Subtask #5
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 17676 KB Output is correct
2 Correct 305 ms 114712 KB Output is correct
3 Correct 286 ms 114472 KB Output is correct
4 Correct 236 ms 114492 KB Output is correct

Subtask #6
0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 28 ms 17676 KB Output is correct
2 Correct 305 ms 114712 KB Output is correct
3 Correct 286 ms 114472 KB Output is correct
4 Correct 236 ms 114492 KB Output is correct
5 Incorrect 28 ms 17664 KB Extra information in the output file
6 Halted 0 ms 0 KB -

Subtask #7
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 17656 KB Output is correct
2 Correct 199 ms 96628 KB Output is correct
3 Correct 268 ms 96676 KB Output is correct

Subtask #8
0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 32 ms 17656 KB Output is correct
2 Correct 199 ms 96628 KB Output is correct
3 Correct 268 ms 96676 KB Output is correct
4 Incorrect 32 ms 17664 KB Extra information in the output file
5 Halted 0 ms 0 KB -

Subtask #9
12.5 / 12.5

# Verdict Execution time Memory Grader output
1 Correct 29 ms 17676 KB Output is correct
2 Correct 309 ms 114596 KB Output is correct
3 Correct 281 ms 114548 KB Output is correct
4 Correct 250 ms 114464 KB Output is correct
5 Correct 33 ms 17668 KB Output is correct
6 Correct 198 ms 96692 KB Output is correct
7 Correct 274 ms 96656 KB Output is correct
8 Correct 316 ms 97984 KB Output is correct
9 Correct 302 ms 97912 KB Output is correct
10 Correct 323 ms 103716 KB Output is correct
11 Correct 375 ms 102244 KB Output is correct

Subtask #10
0 / 12.5

# Verdict Execution time Memory Grader output
1 Correct 29 ms 17676 KB Output is correct
2 Correct 309 ms 114596 KB Output is correct
3 Correct 281 ms 114548 KB Output is correct
4 Correct 250 ms 114464 KB Output is correct
5 Correct 33 ms 17668 KB Output is correct
6 Correct 198 ms 96692 KB Output is correct
7 Correct 274 ms 96656 KB Output is correct
8 Correct 316 ms 97984 KB Output is correct
9 Correct 302 ms 97912 KB Output is correct
10 Correct 323 ms 103716 KB Output is correct
11 Correct 375 ms 102244 KB Output is correct
12 Incorrect 28 ms 17676 KB Extra information in the output file
13 Halted 0 ms 0 KB -

Subtask #11
17.5 / 17.5

# Verdict Execution time Memory Grader output
1 Correct 32 ms 17668 KB Output is correct
2 Correct 44 ms 21316 KB Output is correct
3 Correct 41 ms 21496 KB Output is correct
4 Correct 50 ms 21504 KB Output is correct
5 Correct 62 ms 22008 KB Output is correct
6 Correct 42 ms 21504 KB Output is correct
7 Correct 33 ms 17672 KB Output is correct
8 Correct 258 ms 98572 KB Output is correct
9 Correct 222 ms 98536 KB Output is correct
10 Correct 29 ms 17676 KB Output is correct
11 Correct 291 ms 114596 KB Output is correct
12 Correct 281 ms 114488 KB Output is correct
13 Correct 245 ms 115064 KB Output is correct
14 Correct 32 ms 17660 KB Output is correct
15 Correct 194 ms 96712 KB Output is correct
16 Correct 246 ms 96576 KB Output is correct
17 Correct 299 ms 97980 KB Output is correct
18 Correct 304 ms 97892 KB Output is correct
19 Correct 336 ms 103576 KB Output is correct
20 Correct 389 ms 102392 KB Output is correct
21 Correct 212 ms 98420 KB Output is correct
22 Correct 219 ms 98680 KB Output is correct
23 Correct 247 ms 99444 KB Output is correct
24 Correct 237 ms 99444 KB Output is correct
25 Correct 346 ms 102628 KB Output is correct
26 Correct 259 ms 96700 KB Output is correct
27 Correct 272 ms 96960 KB Output is correct

Subtask #12
0 / 17.5

# Verdict Execution time Memory Grader output
1 Correct 32 ms 17668 KB Output is correct
2 Correct 44 ms 21316 KB Output is correct
3 Correct 41 ms 21496 KB Output is correct
4 Correct 50 ms 21504 KB Output is correct
5 Correct 62 ms 22008 KB Output is correct
6 Correct 42 ms 21504 KB Output is correct
7 Correct 33 ms 17672 KB Output is correct
8 Correct 258 ms 98572 KB Output is correct
9 Correct 222 ms 98536 KB Output is correct
10 Correct 29 ms 17676 KB Output is correct
11 Correct 291 ms 114596 KB Output is correct
12 Correct 281 ms 114488 KB Output is correct
13 Correct 245 ms 115064 KB Output is correct
14 Correct 32 ms 17660 KB Output is correct
15 Correct 194 ms 96712 KB Output is correct
16 Correct 246 ms 96576 KB Output is correct
17 Correct 299 ms 97980 KB Output is correct
18 Correct 304 ms 97892 KB Output is correct
19 Correct 336 ms 103576 KB Output is correct
20 Correct 389 ms 102392 KB Output is correct
21 Correct 212 ms 98420 KB Output is correct
22 Correct 219 ms 98680 KB Output is correct
23 Correct 247 ms 99444 KB Output is correct
24 Correct 237 ms 99444 KB Output is correct
25 Correct 346 ms 102628 KB Output is correct
26 Correct 259 ms 96700 KB Output is correct
27 Correct 272 ms 96960 KB Output is correct
28 Incorrect 38 ms 17604 KB Extra information in the output file
29 Halted 0 ms 0 KB -