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Submission #1080560

# Submission time Handle Problem Language Result Execution time Memory
1080560 2024-08-29T10:58:30 Z Joshua_Andersson Simurgh (IOI17_simurgh) C++14
70 / 100
 442 ms 22368 KB 
#include "simurgh.h"

#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
const ll linf = ll(1e18);

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)

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

struct UF
{
	vi par;
	UF(int n) : par(n)
	{
		rep(i, n)par[i] = i;
	}
	int find(int x) { return x == par[x] ? x : par[x] = find(par[x]); }
	void merge(int a, int b)
	{
		a = find(a); b = find(b);
		if (a == b) return;
		par[b] = a;
	}
};

vi spanning;
const int maxn = 500;
const int maxm = maxn * maxn;
int is_golden[maxm], vis[maxn], parnode[maxn], paredge[maxn];
int depth[maxn], visedge[maxm], maxup[maxn], known[maxm];

vector<p2> up_edges[maxn];
void dfs(int u, vector<vector<p2>>& edges)
{
	repe(e, edges[u])
	{
		if (vis[e.first]) // back edge
		{
			if (visedge[e.second]) continue;
			visedge[e.second] = 1;
			up_edges[u].push_back(e);
			maxup[u] = min(maxup[u], depth[e.first]);
		}
		else
		{
			depth[e.first] = depth[u] + 1;
			visedge[e.second] = 1;
			spanning.push_back(e.second);
			vis[e.first] = 1;
			parnode[e.first] = u;
			paredge[e.first] = e.second;
			dfs(e.first, edges);
			if (maxup[e.first]>=depth[e.first]) // bridge
			{
				is_golden[e.second] = 1;
				known[e.second] = 1;
			}
			maxup[u] = min(maxup[u], maxup[e.first]);
		}
	}
}

vi a, b;
int n;
int forest_query(vi edges)
{
	vi q;
	UF uf(n);
	repe(u, edges)
	{
		q.emplace_back(u);
		if (uf.find(a[u]) == uf.find(b[u])) assert(0);
		uf.merge(a[u], b[u]);
	}
	int num_good = 0;
	repe(s, spanning)
	{
		if (uf.find(a[s]) == uf.find(b[s])) continue;
		uf.merge(a[s], b[s]);
		num_good += is_golden[s];
		q.push_back(s);
	}
	assert(sz(q) < n);
	return count_common_roads(q) - num_good;
}

std::vector<int> find_roads(int N, std::vector<int> A, std::vector<int> B) {
	a = A;
	b = B;
	n = N;
	rep(i, maxn) maxup[i] = int(1e6);
	memset(is_golden, 0, sizeof(is_golden));
	memset(parnode, -1, sizeof(parnode));
	if (n==2)
	{
		return { 0 };
	}
	int m = sz(a);

	vector<vector<p2>> dedges(n);
	rep(i, m)
	{
		dedges[a[i]].emplace_back(b[i], i);
		dedges[b[i]].emplace_back(a[i], i);
	}
	vis[0] = 1;
	parnode[0] = 0;
	depth[0] = 0;
	dfs(0, dedges);
	parnode[0] = -1;
	repp(u, 1, n)
	{
		repe(e, up_edges[u])
		{
			vi cycle = { e.second };

			int num_unknown = 0;

			int v = u;
			while (v != 0 && v != e.first)
			{
				if (!known[paredge[v]]) num_unknown++;
				cycle.push_back(paredge[v]);
				v = parnode[v];
			}
			if (num_unknown == 0) continue;
			
			int mx = 0;
			vector<p2> res;
			rep(i, sz(cycle))
			{
				UF uf(n);
				vi q;
				rep(j, sz(cycle))
				{
					if (i == j) continue;
					q.push_back(cycle[j]);
					uf.merge(a[cycle[j]], b[cycle[j]]);
				}
				repe(u, spanning)
				{
					if (uf.find(a[u]) == uf.find(b[u])) continue;
					uf.merge(a[u], b[u]);
					q.push_back(u);
				}
				if (known[cycle[i]])
				{
					int k = count_common_roads(q);
					if (!is_golden[cycle[i]])
					{
						mx = k;
					}
					else mx = k + 1;
				}
				else
				{
					res.emplace_back(cycle[i], count_common_roads(q));
				}
				mx = max(mx, res.back().second);
			}
			
			repe(v, res)
			{
				if (v.second < mx)
				{
					is_golden[v.first] = 1;
				}
				known[v.first] = 1;
			}
		}
	}
	
	assert(sz(spanning) == n - 1);

	vector<set<int>> edges(n);
	rep(i, m)
	{
		edges[a[i]].insert(i);
		edges[b[i]].insert(i);
	}
	queue<int> leaf;
	vi deg(n);
	rep(i, n)
	{
		deg[i] = forest_query(vi(all(edges[i])));
		if (deg[i] == 1) leaf.push(i);
	}

	vi par(n, -1);
	while (sz(leaf))
	{
		int u = leaf.front();
		leaf.pop();

		if (deg[u] == 0) break;
		assert(deg[u] == 1);
		int lo = -1;
		int hi = sz(edges[u]);
		while (lo+1<hi)
		{
			int mid = (lo + hi) / 2;
			vi q;
			auto start = edges[u].begin();
			rep(i, mid + 1)
			{
				q.push_back(*start);
				start++;
			}
			if (forest_query(q))
			{
				hi = mid;
			}
			else lo = mid;
		}
		auto start = edges[u].begin();
		rep(i, hi) start = next(start);
		int e = *start;
		int v = a[e] == u ? b[e] : a[e];
		edges[v].erase(e);
		deg[v]--;
		if (deg[v]==1)
		{
			leaf.push(v);
		}
		par[u] = e;
	}

	vi r;
	rep(i, n) if (par[i] != -1)r.push_back(par[i]);
	int common = count_common_roads(r);
	assert(common == n - 1);
	return r;
}

Subtask #1
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3164 KB correct
2 Correct 1 ms 3164 KB correct
3 Correct 1 ms 3008 KB correct
4 Correct 1 ms 3164 KB correct
5 Correct 1 ms 3164 KB correct
6 Correct 1 ms 3164 KB correct
7 Correct 1 ms 3164 KB correct
8 Correct 1 ms 3164 KB correct
9 Correct 1 ms 3164 KB correct
10 Correct 1 ms 3164 KB correct
11 Correct 1 ms 3164 KB correct
12 Correct 1 ms 3164 KB correct
13 Correct 1 ms 3164 KB correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3164 KB correct
2 Correct 1 ms 3164 KB correct
3 Correct 1 ms 3008 KB correct
4 Correct 1 ms 3164 KB correct
5 Correct 1 ms 3164 KB correct
6 Correct 1 ms 3164 KB correct
7 Correct 1 ms 3164 KB correct
8 Correct 1 ms 3164 KB correct
9 Correct 1 ms 3164 KB correct
10 Correct 1 ms 3164 KB correct
11 Correct 1 ms 3164 KB correct
12 Correct 1 ms 3164 KB correct
13 Correct 1 ms 3164 KB correct
14 Correct 2 ms 3420 KB correct
15 Correct 2 ms 3420 KB correct
16 Correct 4 ms 3440 KB correct
17 Correct 3 ms 3164 KB correct
18 Correct 1 ms 3164 KB correct
19 Correct 3 ms 3420 KB correct
20 Correct 2 ms 3160 KB correct
21 Correct 2 ms 3160 KB correct
22 Correct 2 ms 3160 KB correct
23 Correct 2 ms 3232 KB correct
24 Correct 2 ms 3164 KB correct
25 Correct 1 ms 3232 KB correct
26 Correct 2 ms 3164 KB correct
27 Correct 2 ms 3164 KB correct
28 Correct 1 ms 3164 KB correct
29 Correct 2 ms 3160 KB correct
30 Correct 2 ms 3160 KB correct
31 Correct 2 ms 3164 KB correct
32 Correct 2 ms 3164 KB correct
33 Correct 2 ms 3164 KB correct

Subtask #3
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3164 KB correct
2 Correct 1 ms 3164 KB correct
3 Correct 1 ms 3008 KB correct
4 Correct 1 ms 3164 KB correct
5 Correct 1 ms 3164 KB correct
6 Correct 1 ms 3164 KB correct
7 Correct 1 ms 3164 KB correct
8 Correct 1 ms 3164 KB correct
9 Correct 1 ms 3164 KB correct
10 Correct 1 ms 3164 KB correct
11 Correct 1 ms 3164 KB correct
12 Correct 1 ms 3164 KB correct
13 Correct 1 ms 3164 KB correct
14 Correct 2 ms 3420 KB correct
15 Correct 2 ms 3420 KB correct
16 Correct 4 ms 3440 KB correct
17 Correct 3 ms 3164 KB correct
18 Correct 1 ms 3164 KB correct
19 Correct 3 ms 3420 KB correct
20 Correct 2 ms 3160 KB correct
21 Correct 2 ms 3160 KB correct
22 Correct 2 ms 3160 KB correct
23 Correct 2 ms 3232 KB correct
24 Correct 2 ms 3164 KB correct
25 Correct 1 ms 3232 KB correct
26 Correct 2 ms 3164 KB correct
27 Correct 2 ms 3164 KB correct
28 Correct 1 ms 3164 KB correct
29 Correct 2 ms 3160 KB correct
30 Correct 2 ms 3160 KB correct
31 Correct 2 ms 3164 KB correct
32 Correct 2 ms 3164 KB correct
33 Correct 2 ms 3164 KB correct
34 Correct 53 ms 7260 KB correct
35 Correct 52 ms 7256 KB correct
36 Correct 48 ms 6268 KB correct
37 Correct 27 ms 3408 KB correct
38 Correct 50 ms 7252 KB correct
39 Correct 47 ms 6748 KB correct
40 Correct 48 ms 6228 KB correct
41 Correct 58 ms 7252 KB correct
42 Correct 55 ms 7464 KB correct
43 Correct 30 ms 5468 KB correct
44 Correct 33 ms 5128 KB correct
45 Correct 27 ms 5236 KB correct
46 Correct 24 ms 4696 KB correct
47 Correct 17 ms 3932 KB correct
48 Correct 6 ms 3332 KB correct
49 Correct 11 ms 3420 KB correct
50 Correct 18 ms 3832 KB correct
51 Correct 31 ms 5212 KB correct
52 Correct 32 ms 4956 KB correct
53 Correct 25 ms 4700 KB correct
54 Correct 34 ms 5520 KB correct
55 Correct 31 ms 5212 KB correct
56 Correct 38 ms 5308 KB correct
57 Correct 32 ms 5212 KB correct

Subtask #4
19.0 / 19.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3164 KB correct
2 Correct 1 ms 3164 KB correct
3 Correct 200 ms 15192 KB correct
4 Correct 405 ms 21076 KB correct
5 Correct 337 ms 22356 KB correct
6 Correct 381 ms 22328 KB correct
7 Correct 357 ms 22216 KB correct
8 Correct 386 ms 22368 KB correct
9 Correct 428 ms 22352 KB correct
10 Correct 442 ms 22344 KB correct
11 Correct 371 ms 22284 KB correct
12 Correct 371 ms 21044 KB correct
13 Correct 1 ms 3164 KB correct
14 Correct 383 ms 22356 KB correct
15 Correct 376 ms 22356 KB correct

Subtask #5
0 / 30.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 3164 KB correct
2 Correct 1 ms 3164 KB correct
3 Correct 1 ms 3008 KB correct
4 Correct 1 ms 3164 KB correct
5 Correct 1 ms 3164 KB correct
6 Correct 1 ms 3164 KB correct
7 Correct 1 ms 3164 KB correct
8 Correct 1 ms 3164 KB correct
9 Correct 1 ms 3164 KB correct
10 Correct 1 ms 3164 KB correct
11 Correct 1 ms 3164 KB correct
12 Correct 1 ms 3164 KB correct
13 Correct 1 ms 3164 KB correct
14 Correct 2 ms 3420 KB correct
15 Correct 2 ms 3420 KB correct
16 Correct 4 ms 3440 KB correct
17 Correct 3 ms 3164 KB correct
18 Correct 1 ms 3164 KB correct
19 Correct 3 ms 3420 KB correct
20 Correct 2 ms 3160 KB correct
21 Correct 2 ms 3160 KB correct
22 Correct 2 ms 3160 KB correct
23 Correct 2 ms 3232 KB correct
24 Correct 2 ms 3164 KB correct
25 Correct 1 ms 3232 KB correct
26 Correct 2 ms 3164 KB correct
27 Correct 2 ms 3164 KB correct
28 Correct 1 ms 3164 KB correct
29 Correct 2 ms 3160 KB correct
30 Correct 2 ms 3160 KB correct
31 Correct 2 ms 3164 KB correct
32 Correct 2 ms 3164 KB correct
33 Correct 2 ms 3164 KB correct
34 Correct 53 ms 7260 KB correct
35 Correct 52 ms 7256 KB correct
36 Correct 48 ms 6268 KB correct
37 Correct 27 ms 3408 KB correct
38 Correct 50 ms 7252 KB correct
39 Correct 47 ms 6748 KB correct
40 Correct 48 ms 6228 KB correct
41 Correct 58 ms 7252 KB correct
42 Correct 55 ms 7464 KB correct
43 Correct 30 ms 5468 KB correct
44 Correct 33 ms 5128 KB correct
45 Correct 27 ms 5236 KB correct
46 Correct 24 ms 4696 KB correct
47 Correct 17 ms 3932 KB correct
48 Correct 6 ms 3332 KB correct
49 Correct 11 ms 3420 KB correct
50 Correct 18 ms 3832 KB correct
51 Correct 31 ms 5212 KB correct
52 Correct 32 ms 4956 KB correct
53 Correct 25 ms 4700 KB correct
54 Correct 34 ms 5520 KB correct
55 Correct 31 ms 5212 KB correct
56 Correct 38 ms 5308 KB correct
57 Correct 32 ms 5212 KB correct
58 Correct 1 ms 3164 KB correct
59 Correct 1 ms 3164 KB correct
60 Correct 200 ms 15192 KB correct
61 Correct 405 ms 21076 KB correct
62 Correct 337 ms 22356 KB correct
63 Correct 381 ms 22328 KB correct
64 Correct 357 ms 22216 KB correct
65 Correct 386 ms 22368 KB correct
66 Correct 428 ms 22352 KB correct
67 Correct 442 ms 22344 KB correct
68 Correct 371 ms 22284 KB correct
69 Correct 371 ms 21044 KB correct
70 Correct 1 ms 3164 KB correct
71 Correct 383 ms 22356 KB correct
72 Correct 376 ms 22356 KB correct
73 Correct 1 ms 3164 KB correct
74 Correct 355 ms 22156 KB correct
75 Incorrect 318 ms 21884 KB WA in grader: NO
76 Halted 0 ms 0 KB -