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Submission #373698

# Submission time Handle Problem Language Result Execution time Memory
373698 2021-03-05T13:09:13 Z luciocf Love Polygon (BOI18_polygon) C++14
29 / 100
 326 ms 13800 KB 
#include <bits/stdc++.h>

using namespace std;

const int maxn = 1e5+10;

int f[maxn];

int comp[maxn], head[maxn], nivel[maxn], cc;
int ini[maxn], fim[maxn];
int mark[maxn];

bool done[maxn];

void dfs(int u)
{
	mark[u] = 1;

	if (mark[f[u]] == 1)
	{
		++cc;
		head[cc] = u, mark[u] = 2;
		ini[cc] = f[u], fim[cc] = u;
		return;
	}

	if (!mark[f[u]]) dfs(f[u]);

	nivel[u] = nivel[f[u]]+1, comp[u] = comp[f[u]];
	mark[u] = 2;
}

int main(void)
{
	int n;
	cin >> n;

	map<string, int> mp;

	int ind = 0;

	for (int i = 1; i <= n; i++)
	{
		string s1, s2;
		cin >> s1 >> s2;

		if (mp.find(s1) == mp.end()) mp[s1] = ++ind;
		if (mp.find(s2) == mp.end()) mp[s2] = ++ind;

		f[mp[s1]] = mp[s2];
	}

	if (n&1)
	{
		cout << "-1\n";
		return 0;
	}

	for (int i = 1; i <= n; i++)
		if (!mark[i])
			dfs(i);

	int ans = n;

	vector<int> v;
	for (int i = 1; i <= n; i++)
		if (nivel[i])
			v.push_back(i);

	sort(v.begin(), v.end(), [&] (int a, int b) {return nivel[a] > nivel[b];});

	for (int i = 1; i <= cc; i++)
	{
		for (int u = ini[cc]; u <= fim[cc]; u++)
		{
			if (done[u] || f[u] == u) continue;

			if (!done[f[u]])
			{
				ans -= (f[f[u]] == u ? 2 : 1);
				done[u] = done[f[u]] = 1;
			}
		}
	}

	for (auto u: v)
	{
		if (done[u]) continue;

		if (!done[f[u]])
		{
			ans--;
			done[u] = done[f[u]] = 1;
		}
	}

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

Subtask #1
0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 364 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Incorrect 1 ms 364 KB Output isn't correct
11 Halted 0 ms 0 KB -

Subtask #2
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Incorrect 1 ms 364 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 320 ms 12132 KB Output is correct
2 Correct 326 ms 12572 KB Output is correct
3 Correct 264 ms 11756 KB Output is correct
4 Correct 304 ms 10372 KB Output is correct
5 Correct 313 ms 13800 KB Output is correct
6 Correct 307 ms 12264 KB Output is correct
7 Correct 303 ms 12136 KB Output is correct
8 Correct 287 ms 12396 KB Output is correct
9 Correct 293 ms 12264 KB Output is correct
10 Correct 246 ms 12020 KB Output is correct
11 Correct 1 ms 364 KB Output is correct
12 Correct 1 ms 364 KB Output is correct
13 Correct 1 ms 364 KB Output is correct
14 Correct 1 ms 364 KB Output is correct

Subtask #4
0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 364 KB Output is correct
2 Correct 1 ms 364 KB Output is correct
3 Correct 1 ms 364 KB Output is correct
4 Correct 1 ms 364 KB Output is correct
5 Correct 1 ms 364 KB Output is correct
6 Correct 1 ms 364 KB Output is correct
7 Correct 1 ms 364 KB Output is correct
8 Correct 1 ms 364 KB Output is correct
9 Correct 1 ms 364 KB Output is correct
10 Incorrect 1 ms 364 KB Output isn't correct
11 Halted 0 ms 0 KB -