oj.uz

Submission #1080568

# Submission time Handle Problem Language Result Execution time Memory
1080568 2024-08-29T11:05:24 Z Elias Simurgh (IOI17_simurgh) C++17
51 / 100
 653 ms 3004 KB 
#ifndef _DEBUG
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#endif

#include <bits/stdc++.h>

using namespace std;


#ifdef _DEBUG
std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v);
int count_common_roads(const std::vector<int> &r);
#else
#include "simurgh.h"
#endif

vector<int> U, V;
int N;

vector<int> trash_edges, fancy_edges;

vector<int> par;

int find_parent(int a)
{
	if (par[a] == a)
		return a;
	return par[a] = find_parent(par[a]);
}

bool unite(int a, int b)
{
	if (rand() % 2)
		swap(a, b);

	a = find_parent(a), b = find_parent(b);
	if (a == b)
		return false;
	par[b] = a;
	return true;
}

void reset_parent()
{
	par = vector<int>(N);
	for (int i = 0; i < N; i++)
		par[i] = i;
}

void dfs_spanning(unordered_set<int> &edges)
{
}

bool dfs_cycle(int i, int p, vector<vector<pair<int, int>>> &adj, vector<int> &vis, unordered_set<int> &edges)
{
	vis[i] = true;

	for (auto [c, j] : adj[i])
	{
		if (c == p)
			continue;
		if (vis[c] || dfs_cycle(c, i, adj, vis, edges))
		{
			edges.insert(j);
			return true;
		}
	}
	return false;
}

int cnt_common_set(unordered_set<int> &a)
{
	// if (results.count(a))
	// 	return results[a];
	return count_common_roads(vector(a.begin(), a.end()));
}

vector<vector<pair<int, int>>> build_adj(unordered_set<int> &edges)
{
	vector<vector<pair<int, int>>> adj(N);
	for (int i : edges)
	{
		adj[U[i]].push_back({V[i], i});
		adj[V[i]].push_back({U[i], i});
	}
	return adj;
}

std::vector<int> find_roads(int n, std::vector<int> u, std::vector<int> v)
{
	U = u, V = v;
	N = n;

	fancy_edges = trash_edges = vector<int>(u.size());

	unordered_set<int> edges;

	vector<int> visited(n);

	reset_parent();
	for (int i = 0; i < U.size(); i++)
	{
		if (unite(U[i], V[i]))
			edges.insert(i);
	}

	int base_count = cnt_common_set(edges);

	for (int i = 0; i < u.size(); i++)
	{
		if (edges.count(i) || fancy_edges[i] || trash_edges[i])
			continue;

		edges.insert(i);

		auto adj = build_adj(edges);
		visited = vector<int>(n);

		unordered_set<int> cycle_edges;

		dfs_cycle(u[i], -1, adj, visited, cycle_edges);

		cycle_edges.erase(i);

		vector<int> stayed;
		int action_stayed = 0;

		for (int edge : cycle_edges)
		{
			if (fancy_edges[edge])
				continue;

			edges.erase(edge);

			int new_count = cnt_common_set(edges);

			if (new_count > base_count)
			{ // better than other edge
				trash_edges[edge] = true;

				fancy_edges[i] = true;
				edges.insert(i);
				action_stayed = 1;

				base_count = new_count;
				break;
			}
			else if (new_count < base_count)
			{
				trash_edges[i] = true;
				edges.erase(i);
				action_stayed = -1;

				edges.insert(edge);
				fancy_edges[edge] = true;
				break;
			}
			else
			{
				if (trash_edges[edge])
				{
					trash_edges[i] = true;
					edges.insert(i);

					action_stayed = -1;
					break;
				}
				else
				{
					edges.insert(edge);
					stayed.push_back(edge);
				}
			}
		}

		if (action_stayed == 0)
		{
			trash_edges[i] = true;
			edges.erase(i);
			for (int edge : stayed)
				trash_edges[edge] = true;
		}
		else if (action_stayed == 1)
		{
			for (int edge : stayed)
				fancy_edges[edge] = true;
		}
		else if (action_stayed == -1)
		{
			for (int edge : stayed)
				trash_edges[edge] = true;
		}
	}

	for (auto edge : edges)
		fancy_edges[edge] = true;

	vector<int> fancy;

	for (int i = 0; i < u.size(); i++)
		if (fancy_edges[i])
			fancy.push_back(i);

	return fancy;
}

#ifdef _DEBUG

using namespace std;

static int MAXQ = 30000;

static int n, m, q = 0;
static vector<int> u, v;
static vector<bool> goal;
static vector<int> parent;

static int find(int node)
{
	return (parent[node] == node ? node : parent[node] = find(parent[node]));
}

static bool merge(int v1, int v2)
{
	v1 = find(v1);
	v2 = find(v2);
	if (v1 == v2)
		return false;
	parent[v1] = v2;
	return true;
}

static void wrong_answer()
{
	printf("NO\n");
	exit(0);
}

static bool is_valid(const vector<int> &r)
{
	if (int(r.size()) != n - 1)
		return false;

	for (int i = 0; i < n - 1; i++)
		if (r[i] < 0 || r[i] >= m)
			return false;

	parent.resize(n);
	for (int i = 0; i < n; i++)
	{
		parent[i] = i;
	}
	for (int i = 0; i < n - 1; i++)
	{
		if (!merge(u[r[i]], v[r[i]]))
		{
			return false;
		}
	}
	return true;
}

static int _count_common_roads_internal(const vector<int> &r)
{
	if (!is_valid(r))
		wrong_answer();

	int common = 0;
	for (int i = 0; i < n - 1; i++)
	{
		bool is_common = goal[r[i]];
		if (is_common)
			common++;
	}

	return common;
}

int count_common_roads(const vector<int> &r)
{
	q++;
	if (q > MAXQ)
	{
		cout << "Too many queries!!!\n";
		wrong_answer();
	}

	return _count_common_roads_internal(r);
}

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

	freopen("/home/elias/Downloads/ioi2017tests/simurgh/tests/3-01.in", "r", stdin);

	string trash;
	cin >> trash;

	assert(2 == scanf("%d %d", &n, &m));
	assert(1 == scanf("%d", &MAXQ));

	u.resize(m);
	v.resize(m);

	for (int i = 0; i < m; i++)
		assert(2 == scanf("%d %d", &u[i], &v[i]));

	goal.resize(m, false);

	for (int i = 0; i < n - 1; i++)
	{
		int id;
		assert(1 == scanf("%d", &id));
		goal[id] = true;
	}

	vector<int> result = find_roads(n, u, v);

	if (_count_common_roads_internal(result) != n - 1)
		wrong_answer();

	printf("OK\n");
	for (int i = 0; i < (int)result.size(); i++)
	{
		if (i)
			printf(" ");
		printf("%d", result[i]);
	}
	printf("\n");

	cout << q << "\n";

	return 0;
}

#endif

Compilation message

simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:102:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  102 |  for (int i = 0; i < U.size(); i++)
      |                  ~~^~~~~~~~~~
simurgh.cpp:110:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  110 |  for (int i = 0; i < u.size(); i++)
      |                  ~~^~~~~~~~~~
simurgh.cpp:201:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  201 |  for (int i = 0; i < u.size(); i++)
      |                  ~~^~~~~~~~~~

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB correct
2 Correct 0 ms 348 KB correct
3 Correct 0 ms 348 KB correct
4 Correct 0 ms 348 KB correct
5 Correct 0 ms 348 KB correct
6 Correct 0 ms 348 KB correct
7 Correct 0 ms 348 KB correct
8 Correct 0 ms 348 KB correct
9 Correct 0 ms 348 KB correct
10 Correct 0 ms 348 KB correct
11 Correct 0 ms 348 KB correct
12 Correct 1 ms 348 KB correct
13 Correct 0 ms 348 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB correct
2 Correct 0 ms 348 KB correct
3 Correct 0 ms 348 KB correct
4 Correct 0 ms 348 KB correct
5 Correct 0 ms 348 KB correct
6 Correct 0 ms 348 KB correct
7 Correct 0 ms 348 KB correct
8 Correct 0 ms 348 KB correct
9 Correct 0 ms 348 KB correct
10 Correct 0 ms 348 KB correct
11 Correct 0 ms 348 KB correct
12 Correct 1 ms 348 KB correct
13 Correct 0 ms 348 KB correct
14 Correct 6 ms 348 KB correct
15 Correct 5 ms 348 KB correct
16 Correct 5 ms 348 KB correct
17 Correct 5 ms 480 KB correct
18 Correct 2 ms 348 KB correct
19 Correct 8 ms 348 KB correct
20 Correct 8 ms 344 KB correct
21 Correct 4 ms 348 KB correct
22 Correct 5 ms 408 KB correct
23 Correct 5 ms 348 KB correct
24 Correct 2 ms 348 KB correct
25 Correct 1 ms 348 KB correct
26 Correct 3 ms 348 KB correct
27 Correct 3 ms 344 KB correct
28 Correct 1 ms 348 KB correct
29 Correct 1 ms 348 KB correct
30 Correct 3 ms 348 KB correct
31 Correct 3 ms 348 KB correct
32 Correct 3 ms 348 KB correct
33 Correct 3 ms 460 KB correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB correct
2 Correct 0 ms 348 KB correct
3 Correct 0 ms 348 KB correct
4 Correct 0 ms 348 KB correct
5 Correct 0 ms 348 KB correct
6 Correct 0 ms 348 KB correct
7 Correct 0 ms 348 KB correct
8 Correct 0 ms 348 KB correct
9 Correct 0 ms 348 KB correct
10 Correct 0 ms 348 KB correct
11 Correct 0 ms 348 KB correct
12 Correct 1 ms 348 KB correct
13 Correct 0 ms 348 KB correct
14 Correct 6 ms 348 KB correct
15 Correct 5 ms 348 KB correct
16 Correct 5 ms 348 KB correct
17 Correct 5 ms 480 KB correct
18 Correct 2 ms 348 KB correct
19 Correct 8 ms 348 KB correct
20 Correct 8 ms 344 KB correct
21 Correct 4 ms 348 KB correct
22 Correct 5 ms 408 KB correct
23 Correct 5 ms 348 KB correct
24 Correct 2 ms 348 KB correct
25 Correct 1 ms 348 KB correct
26 Correct 3 ms 348 KB correct
27 Correct 3 ms 344 KB correct
28 Correct 1 ms 348 KB correct
29 Correct 1 ms 348 KB correct
30 Correct 3 ms 348 KB correct
31 Correct 3 ms 348 KB correct
32 Correct 3 ms 348 KB correct
33 Correct 3 ms 460 KB correct
34 Correct 648 ms 1112 KB correct
35 Correct 613 ms 1112 KB correct
36 Correct 397 ms 860 KB correct
37 Correct 21 ms 344 KB correct
38 Correct 653 ms 1116 KB correct
39 Correct 501 ms 1112 KB correct
40 Correct 364 ms 1056 KB correct
41 Correct 506 ms 1348 KB correct
42 Correct 508 ms 1116 KB correct
43 Correct 239 ms 1108 KB correct
44 Correct 233 ms 824 KB correct
45 Correct 254 ms 1108 KB correct
46 Correct 182 ms 604 KB correct
47 Correct 79 ms 604 KB correct
48 Correct 4 ms 348 KB correct
49 Correct 21 ms 512 KB correct
50 Correct 74 ms 604 KB correct
51 Correct 241 ms 856 KB correct
52 Correct 185 ms 600 KB correct
53 Correct 212 ms 600 KB correct
54 Correct 227 ms 856 KB correct
55 Correct 274 ms 856 KB correct
56 Correct 285 ms 860 KB correct
57 Correct 246 ms 860 KB correct

Subtask #4
0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB correct
2 Correct 0 ms 348 KB correct
3 Incorrect 454 ms 3004 KB WA in grader: NO
4 Halted 0 ms 0 KB -

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB correct
2 Correct 0 ms 348 KB correct
3 Correct 0 ms 348 KB correct
4 Correct 0 ms 348 KB correct
5 Correct 0 ms 348 KB correct
6 Correct 0 ms 348 KB correct
7 Correct 0 ms 348 KB correct
8 Correct 0 ms 348 KB correct
9 Correct 0 ms 348 KB correct
10 Correct 0 ms 348 KB correct
11 Correct 0 ms 348 KB correct
12 Correct 1 ms 348 KB correct
13 Correct 0 ms 348 KB correct
14 Correct 6 ms 348 KB correct
15 Correct 5 ms 348 KB correct
16 Correct 5 ms 348 KB correct
17 Correct 5 ms 480 KB correct
18 Correct 2 ms 348 KB correct
19 Correct 8 ms 348 KB correct
20 Correct 8 ms 344 KB correct
21 Correct 4 ms 348 KB correct
22 Correct 5 ms 408 KB correct
23 Correct 5 ms 348 KB correct
24 Correct 2 ms 348 KB correct
25 Correct 1 ms 348 KB correct
26 Correct 3 ms 348 KB correct
27 Correct 3 ms 344 KB correct
28 Correct 1 ms 348 KB correct
29 Correct 1 ms 348 KB correct
30 Correct 3 ms 348 KB correct
31 Correct 3 ms 348 KB correct
32 Correct 3 ms 348 KB correct
33 Correct 3 ms 460 KB correct
34 Correct 648 ms 1112 KB correct
35 Correct 613 ms 1112 KB correct
36 Correct 397 ms 860 KB correct
37 Correct 21 ms 344 KB correct
38 Correct 653 ms 1116 KB correct
39 Correct 501 ms 1112 KB correct
40 Correct 364 ms 1056 KB correct
41 Correct 506 ms 1348 KB correct
42 Correct 508 ms 1116 KB correct
43 Correct 239 ms 1108 KB correct
44 Correct 233 ms 824 KB correct
45 Correct 254 ms 1108 KB correct
46 Correct 182 ms 604 KB correct
47 Correct 79 ms 604 KB correct
48 Correct 4 ms 348 KB correct
49 Correct 21 ms 512 KB correct
50 Correct 74 ms 604 KB correct
51 Correct 241 ms 856 KB correct
52 Correct 185 ms 600 KB correct
53 Correct 212 ms 600 KB correct
54 Correct 227 ms 856 KB correct
55 Correct 274 ms 856 KB correct
56 Correct 285 ms 860 KB correct
57 Correct 246 ms 860 KB correct
58 Correct 0 ms 348 KB correct
59 Correct 0 ms 348 KB correct
60 Incorrect 454 ms 3004 KB WA in grader: NO
61 Halted 0 ms 0 KB -