oj.uz

Submission #939431

# Submission time Handle Problem Language Result Execution time Memory
939431 2024-03-06T11:05:06 Z Gromp15 Love Polygon (BOI18_polygon) C++17
100 / 100
 300 ms 19916 KB 
#include <bits/stdc++.h>
#define ll long long
#define ar array
#define db double
#define all(x) x.begin(), x.end()
#define sz(x) (int)x.size()
using namespace std;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define rint(l, r) uniform_int_distribution<int>(l, r)(rng)
template<typename T> bool ckmin(T &a, const T &b) { return a > b ? a = b, 1 : 0; }
template<typename T> bool ckmax(T &a, const T &b) { return a < b ? a = b, 1 : 0; }
void test_case() {
	int n; cin >> n;
	map<string, int> mp;
	vector<int> a(n);
	vector<vector<int>> adj2(n);
	vector<int> indeg(n);
	for (int i = 0; i < n; i++) {
		string s, t;
		cin >> s >> t;
		if (!mp.count(s)) mp[s] = mp.size();
		if (!mp.count(t)) mp[t] = mp.size();
		a[mp[s]] = mp[t];
		adj2[mp[s]].push_back(mp[t]);
		adj2[mp[t]].push_back(mp[s]);
		indeg[mp[t]]++;
	}
	if (n & 1) {
		cout << -1 << '\n'; return;
	}
	vector<bool> vis(n), dir(n), vis3(n), in_ccl(n);
	for (int i = 0; i < n; i++) {
		if (i != a[i] && a[a[i]] == i) {
			dir[i] = dir[a[i]] = 1;
		}
	}
	int ans = 0, extra = 0;
	for (int i = 0; i < n; i++) if (!vis[i]) {
		vector<int> got;
		queue<int> q;
		auto dfs = [&](auto&& s, int v) -> void {
			got.emplace_back(v);
			vis[v] = 1;
			if (!indeg[v]) q.push(v);
			for (int u : adj2[v]) if (!vis[u]) s(s, u);
		};
		dfs(dfs, i);
		while (q.size()) {
			int v = q.front(); q.pop();
			if (dir[v]) {
				if (--indeg[a[v]] == 0) q.push(a[v]);
				continue;
			}
			int nxt = a[v];
			if (!dir[nxt]) {
				dir[nxt] = dir[v] = 1;
				ans++;
			}
			else {
				dir[v] = 1;
				extra++;
				// we need to find someone else
			}
			if (--indeg[nxt] == 0) q.push(nxt);
		}
		int to = i;
		while (!vis3[to]) vis3[to] = 1, to = a[to];
		while (!in_ccl[to]) in_ccl[to] = 1, to = a[to];
		int starting = -1, sx = -1;
		for (int v : got) if (in_ccl[v]) {
			sx = v;
			if (dir[v] && !dir[a[v]]) {
				starting = v; break;
			}
		}
		// if we dont have, then arbitrary is fine
		assert(~sx);
		if (!~starting) starting = sx;
		int v = starting;
		for (int i = 0; i < sz(got); i++, v = a[v]) if (!dir[v]) {
			int nxt = a[v];
			if (v == nxt) {
				dir[v] = 1;
				extra++; continue;
			}
			if (!dir[nxt]) {
				dir[nxt] = dir[v] = 1;
				ans += a[nxt] != v;
			}
			else { 
				dir[v] = 1;
				extra++;
			}
		}
	}
	cout << ans + extra << '\n';



}
int main() {
    cin.tie(0)->sync_with_stdio(0);
    int t = 1;
//    cin >> t;
    while (t--) test_case();
}

Subtask #1
21.0 / 21.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 356 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 600 KB Output is correct

Subtask #2
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 344 KB Output is correct
4 Correct 251 ms 17272 KB Output is correct
5 Correct 271 ms 15060 KB Output is correct
6 Correct 246 ms 17548 KB Output is correct
7 Correct 252 ms 14444 KB Output is correct

Subtask #3
29.0 / 29.0

# Verdict Execution time Memory Grader output
1 Correct 261 ms 14672 KB Output is correct
2 Correct 244 ms 17756 KB Output is correct
3 Correct 218 ms 16948 KB Output is correct
4 Correct 228 ms 16720 KB Output is correct
5 Correct 236 ms 18660 KB Output is correct
6 Correct 261 ms 17552 KB Output is correct
7 Correct 261 ms 17104 KB Output is correct
8 Correct 273 ms 16724 KB Output is correct
9 Correct 232 ms 17428 KB Output is correct
10 Correct 207 ms 17848 KB Output is correct
11 Correct 0 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 0 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct

Subtask #4
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 344 KB Output is correct
3 Correct 1 ms 348 KB Output is correct
4 Correct 0 ms 348 KB Output is correct
5 Correct 1 ms 356 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 348 KB Output is correct
9 Correct 0 ms 348 KB Output is correct
10 Correct 0 ms 348 KB Output is correct
11 Correct 1 ms 348 KB Output is correct
12 Correct 0 ms 348 KB Output is correct
13 Correct 1 ms 348 KB Output is correct
14 Correct 0 ms 348 KB Output is correct
15 Correct 1 ms 600 KB Output is correct
16 Correct 0 ms 348 KB Output is correct
17 Correct 0 ms 344 KB Output is correct
18 Correct 1 ms 344 KB Output is correct
19 Correct 251 ms 17272 KB Output is correct
20 Correct 271 ms 15060 KB Output is correct
21 Correct 246 ms 17548 KB Output is correct
22 Correct 252 ms 14444 KB Output is correct
23 Correct 261 ms 14672 KB Output is correct
24 Correct 244 ms 17756 KB Output is correct
25 Correct 218 ms 16948 KB Output is correct
26 Correct 228 ms 16720 KB Output is correct
27 Correct 236 ms 18660 KB Output is correct
28 Correct 261 ms 17552 KB Output is correct
29 Correct 261 ms 17104 KB Output is correct
30 Correct 273 ms 16724 KB Output is correct
31 Correct 232 ms 17428 KB Output is correct
32 Correct 207 ms 17848 KB Output is correct
33 Correct 0 ms 348 KB Output is correct
34 Correct 0 ms 348 KB Output is correct
35 Correct 0 ms 348 KB Output is correct
36 Correct 0 ms 348 KB Output is correct
37 Correct 268 ms 17056 KB Output is correct
38 Correct 246 ms 17648 KB Output is correct
39 Correct 255 ms 16728 KB Output is correct
40 Correct 240 ms 17428 KB Output is correct
41 Correct 239 ms 16852 KB Output is correct
42 Correct 263 ms 17360 KB Output is correct
43 Correct 249 ms 17104 KB Output is correct
44 Correct 300 ms 17248 KB Output is correct
45 Correct 246 ms 17340 KB Output is correct
46 Correct 265 ms 17292 KB Output is correct
47 Correct 226 ms 17760 KB Output is correct
48 Correct 264 ms 16728 KB Output is correct
49 Correct 246 ms 17832 KB Output is correct
50 Correct 209 ms 16736 KB Output is correct
51 Correct 244 ms 16592 KB Output is correct
52 Correct 275 ms 18564 KB Output is correct
53 Correct 236 ms 17432 KB Output is correct
54 Correct 242 ms 16724 KB Output is correct
55 Correct 247 ms 16728 KB Output is correct
56 Correct 227 ms 17540 KB Output is correct
57 Correct 161 ms 17912 KB Output is correct
58 Correct 1 ms 344 KB Output is correct
59 Correct 0 ms 348 KB Output is correct
60 Correct 0 ms 348 KB Output is correct
61 Correct 0 ms 348 KB Output is correct
62 Correct 0 ms 348 KB Output is correct
63 Correct 0 ms 348 KB Output is correct
64 Correct 0 ms 348 KB Output is correct
65 Correct 265 ms 19328 KB Output is correct
66 Correct 271 ms 16580 KB Output is correct
67 Correct 243 ms 19916 KB Output is correct
68 Correct 246 ms 16776 KB Output is correct
69 Correct 1 ms 348 KB Output is correct
70 Correct 0 ms 348 KB Output is correct
71 Correct 0 ms 344 KB Output is correct
72 Correct 0 ms 348 KB Output is correct
73 Correct 0 ms 348 KB Output is correct
74 Correct 0 ms 348 KB Output is correct
75 Correct 0 ms 348 KB Output is correct
76 Correct 0 ms 348 KB Output is correct
77 Correct 0 ms 348 KB Output is correct
78 Correct 0 ms 348 KB Output is correct
79 Correct 0 ms 460 KB Output is correct
80 Correct 1 ms 348 KB Output is correct
81 Correct 0 ms 348 KB Output is correct
82 Correct 0 ms 348 KB Output is correct
83 Correct 0 ms 348 KB Output is correct