oj.uz

Submission #105092

# Submission time Handle Problem Language Result Execution time Memory
105092 2019-04-10T14:20:52 Z eriksuenderhauf Parachute rings (IOI12_rings) C++11
100 / 100
 1944 ms 101076 KB 
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
//#include "grader.h"
#define pii pair<int,int>
#define vi vector<int>
#define vii vector<pii>
#define pb push_back
using namespace std;
const int MAXN = 1e6 + 5;
int par[MAXN], deg[MAXN], cycle = 0, cnt[MAXN], n = 0;
int mrk[MAXN];
vi cand, adj[MAXN];

struct DSU {
	int par[MAXN], deg[MAXN], root = 0;
	bool valid = true;
	int qry(int x) {
		if (!valid) return 0;
		return x == par[x] ? x : par[x] = qry(par[x]);
	}

	void join(int u, int v) {
		if (!valid) return;
		u = qry(u), v = qry(v);
		par[u] = v;
	}

	void init(int n) {
		for (int i = 0; i < n; i++)
			par[i] = i;
	}
} e, f;

int qry(int x) {
	return x == par[x] ? x : par[x] = qry(par[x]);
}

void join(int u, int v) {
	u = qry(u), v = qry(v);
	par[u] = v;
}

void Init(int N) {
	n = N;
	for (int i = 0; i < N; i++) {
		par[i] = i;
		cand.pb(i);
		mrk[i] = 1;
	}
}

void do3(int b) {
	vi tmp;
	for (int v: adj[b])
		if (mrk[v])
			tmp.pb(v);
	if (mrk[b])
		tmp.pb(b);
	for (int v: cand)
		mrk[v] = 0;
	for (int v: tmp)
		mrk[v] = 1;
	cand = tmp;
}

int par2[MAXN];
bool fin = false;
vii edg;

void dfs(int u, int p) {
	par2[u] = p;
	for (int v: adj[u])
		if (v != p)
			dfs(v, u);
}

void addE(int u, int v) {
	if (u == e.root || v == e.root || e.valid == false) return;
	e.deg[u]++, e.deg[v]++;
	if (e.qry(u) == e.qry(v) || e.deg[u] > 2 || e.deg[v] > 2)
		e.valid = false;
	e.join(u, v);
}
void addF(int u, int v) {
	if (u == f.root || v == f.root || f.valid == false) return;
	f.deg[u]++, f.deg[v]++;
	if (f.qry(u) == f.qry(v) || f.deg[u] > 2 || f.deg[v] > 2)
		f.valid = false;
	f.join(u, v);
}

void Link(int a, int b) {
	if (cand.empty()) return;
	if (fin) {
		addE(a, b);
		addF(a, b);
		return;
	}
	edg.pb({a, b});
	int delta = 0;
	if (qry(a) == qry(b) && cycle == 0) {
		dfs(a, -1);
		vi tmp = {a};
		int u = b;
		while (u != a) {
			tmp.pb(u);
			u = par2[u];
		}
		vi nx;
		for (int i: tmp)
			if (mrk[i] == 1) {
				nx.pb(i);
				mrk[i] = 2;
			}
		for (int i: cand)
			mrk[i]--;
		cand = nx;
	}
	adj[a].pb(b);
	adj[b].pb(a);
	if (qry(a) == qry(b)) {
		delta++;
		cycle++;
	}
	cnt[deg[a]]--;
	cnt[deg[b]]--;
	deg[a]++, deg[b]++;
	cnt[deg[a]]++;
	cnt[deg[b]]++;
	if (cnt[4] > 1) {
		cand = {};
		return;
	}
	if (deg[a] > deg[b])
		swap(a, b);
	if (deg[b] == 3) do3(b);
	if (deg[a] == 3) do3(a);
	if (deg[b] == 4) {
		if (!mrk[b]) {
			cand = {};
			return;
		}
		memset(mrk, 0, sizeof mrk);
		mrk[b] = 1;
		cand = {b};
	}
	join(a, b);
	if (cand.empty()) return;
	if (cycle > 1 && delta > 0) {
		if (qry(a) != qry(cand[0])) {
			cand = {};
			return;
		}
		if (mrk[a] && mrk[b]) {
			cand = {a, b};
			memset(mrk, 0, sizeof mrk);
			mrk[a] = 1, mrk[b] = 1;
		} else if (mrk[a] || mrk[b]) {
			if (mrk[a]) {
				memset(mrk, 0, sizeof mrk);
				mrk[a] = 1;
				cand = {a};
			} else {
				memset(mrk, 0, sizeof mrk);
				mrk[b] = 1;
				cand = {b};
			}
		}
		fin = true;
		if (cand.size() == 1) {
			f.valid = false;
			e.init(n);
			e.root = cand[0];
			for (int i = 0; i < edg.size(); i++) {
				int u, v;
				tie(u, v) = edg[i];
				if (u == cand[0] || v == cand[0]) continue;
				e.deg[u]++, e.deg[v]++;
				if (e.qry(u) == e.qry(v) || e.deg[u] > 2 || e.deg[v] > 2) {
					cand = {};
					return;
				}
				e.join(u, v);
			}
		} else {
			e.init(n);
			e.root = cand[0];
			for (int i = 0; e.valid && i < edg.size(); i++) {
				int u, v;
				tie(u, v) = edg[i];
				if (u == cand[0] || v == cand[0]) continue;
				e.deg[u]++, e.deg[v]++;
				if (e.qry(u) == e.qry(v) || e.deg[u] > 2 || e.deg[v] > 2)
					e.valid = false;
				e.join(u, v);
			}
			f.init(n);
			f.root = cand[1];
			for (int i = 0; f.valid && i < edg.size(); i++) {
				int u, v;
				tie(u, v) = edg[i];
				if (u == cand[1] || v == cand[1]) continue;
				f.deg[u]++, f.deg[v]++;
				if (f.qry(u) == f.qry(v) || f.deg[u] > 2 || f.deg[v] > 2)
					f.valid = false;
				f.join(u, v);
			}
		}
	}
}

int CountCritical() {
	int ret = 0;
	if (fin) {
		ret += (e.valid ? 1 : 0);
		ret += (f.valid ? 1 : 0);
		return ret;
	}
	return cand.size();
}

Compilation message

rings.cpp: In function 'void Link(int, int)':
rings.cpp:174:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 0; i < edg.size(); i++) {
                    ~~^~~~~~~~~~~~
rings.cpp:188:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 0; e.valid && i < edg.size(); i++) {
                               ~~^~~~~~~~~~~~
rings.cpp:199:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 0; f.valid && i < edg.size(); i++) {
                               ~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23808 KB Output is correct
2 Correct 35 ms 28024 KB Output is correct
3 Correct 32 ms 28160 KB Output is correct
4 Correct 31 ms 23904 KB Output is correct
5 Correct 31 ms 24056 KB Output is correct
6 Correct 34 ms 24312 KB Output is correct
7 Correct 26 ms 23936 KB Output is correct
8 Correct 30 ms 24184 KB Output is correct
9 Correct 30 ms 24184 KB Output is correct
10 Correct 32 ms 24184 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 643 ms 52396 KB Output is correct
2 Correct 1337 ms 68608 KB Output is correct
3 Correct 410 ms 40220 KB Output is correct
4 Correct 1614 ms 80332 KB Output is correct
5 Correct 1630 ms 83784 KB Output is correct
6 Correct 1944 ms 101076 KB Output is correct
7 Correct 335 ms 40368 KB Output is correct
8 Correct 1503 ms 75436 KB Output is correct
9 Correct 1676 ms 78796 KB Output is correct
10 Correct 1037 ms 78492 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23808 KB Output is correct
2 Correct 35 ms 28024 KB Output is correct
3 Correct 32 ms 28160 KB Output is correct
4 Correct 31 ms 23904 KB Output is correct
5 Correct 31 ms 24056 KB Output is correct
6 Correct 34 ms 24312 KB Output is correct
7 Correct 26 ms 23936 KB Output is correct
8 Correct 30 ms 24184 KB Output is correct
9 Correct 30 ms 24184 KB Output is correct
10 Correct 32 ms 24184 KB Output is correct
11 Correct 34 ms 28152 KB Output is correct
12 Correct 36 ms 24600 KB Output is correct
13 Correct 38 ms 28412 KB Output is correct
14 Correct 35 ms 28200 KB Output is correct
15 Correct 36 ms 28568 KB Output is correct
16 Correct 31 ms 24576 KB Output is correct
17 Correct 29 ms 24184 KB Output is correct
18 Correct 29 ms 24440 KB Output is correct
19 Correct 33 ms 24748 KB Output is correct
20 Correct 34 ms 24576 KB Output is correct

Subtask #4
14.0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23808 KB Output is correct
2 Correct 35 ms 28024 KB Output is correct
3 Correct 32 ms 28160 KB Output is correct
4 Correct 31 ms 23904 KB Output is correct
5 Correct 31 ms 24056 KB Output is correct
6 Correct 34 ms 24312 KB Output is correct
7 Correct 26 ms 23936 KB Output is correct
8 Correct 30 ms 24184 KB Output is correct
9 Correct 30 ms 24184 KB Output is correct
10 Correct 32 ms 24184 KB Output is correct
11 Correct 34 ms 28152 KB Output is correct
12 Correct 36 ms 24600 KB Output is correct
13 Correct 38 ms 28412 KB Output is correct
14 Correct 35 ms 28200 KB Output is correct
15 Correct 36 ms 28568 KB Output is correct
16 Correct 31 ms 24576 KB Output is correct
17 Correct 29 ms 24184 KB Output is correct
18 Correct 29 ms 24440 KB Output is correct
19 Correct 33 ms 24748 KB Output is correct
20 Correct 34 ms 24576 KB Output is correct
21 Correct 51 ms 26228 KB Output is correct
22 Correct 70 ms 27380 KB Output is correct
23 Correct 81 ms 28280 KB Output is correct
24 Correct 73 ms 30624 KB Output is correct
25 Correct 48 ms 30584 KB Output is correct
26 Correct 86 ms 32212 KB Output is correct
27 Correct 109 ms 28788 KB Output is correct
28 Correct 55 ms 25856 KB Output is correct
29 Correct 55 ms 26100 KB Output is correct
30 Correct 185 ms 30496 KB Output is correct

Subtask #5
31.0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 25 ms 23808 KB Output is correct
2 Correct 35 ms 28024 KB Output is correct
3 Correct 32 ms 28160 KB Output is correct
4 Correct 31 ms 23904 KB Output is correct
5 Correct 31 ms 24056 KB Output is correct
6 Correct 34 ms 24312 KB Output is correct
7 Correct 26 ms 23936 KB Output is correct
8 Correct 30 ms 24184 KB Output is correct
9 Correct 30 ms 24184 KB Output is correct
10 Correct 32 ms 24184 KB Output is correct
11 Correct 643 ms 52396 KB Output is correct
12 Correct 1337 ms 68608 KB Output is correct
13 Correct 410 ms 40220 KB Output is correct
14 Correct 1614 ms 80332 KB Output is correct
15 Correct 1630 ms 83784 KB Output is correct
16 Correct 1944 ms 101076 KB Output is correct
17 Correct 335 ms 40368 KB Output is correct
18 Correct 1503 ms 75436 KB Output is correct
19 Correct 1676 ms 78796 KB Output is correct
20 Correct 1037 ms 78492 KB Output is correct
21 Correct 34 ms 28152 KB Output is correct
22 Correct 36 ms 24600 KB Output is correct
23 Correct 38 ms 28412 KB Output is correct
24 Correct 35 ms 28200 KB Output is correct
25 Correct 36 ms 28568 KB Output is correct
26 Correct 31 ms 24576 KB Output is correct
27 Correct 29 ms 24184 KB Output is correct
28 Correct 29 ms 24440 KB Output is correct
29 Correct 33 ms 24748 KB Output is correct
30 Correct 34 ms 24576 KB Output is correct
31 Correct 51 ms 26228 KB Output is correct
32 Correct 70 ms 27380 KB Output is correct
33 Correct 81 ms 28280 KB Output is correct
34 Correct 73 ms 30624 KB Output is correct
35 Correct 48 ms 30584 KB Output is correct
36 Correct 86 ms 32212 KB Output is correct
37 Correct 109 ms 28788 KB Output is correct
38 Correct 55 ms 25856 KB Output is correct
39 Correct 55 ms 26100 KB Output is correct
40 Correct 185 ms 30496 KB Output is correct
41 Correct 283 ms 42100 KB Output is correct
42 Correct 668 ms 56596 KB Output is correct
43 Correct 288 ms 50560 KB Output is correct
44 Correct 318 ms 40544 KB Output is correct
45 Correct 483 ms 53216 KB Output is correct
46 Correct 903 ms 69976 KB Output is correct
47 Correct 1522 ms 86768 KB Output is correct
48 Correct 300 ms 42208 KB Output is correct
49 Correct 938 ms 70876 KB Output is correct
50 Correct 1069 ms 70428 KB Output is correct
51 Correct 369 ms 50736 KB Output is correct
52 Correct 295 ms 37296 KB Output is correct
53 Correct 254 ms 41436 KB Output is correct
54 Correct 1225 ms 69024 KB Output is correct
55 Correct 1372 ms 73188 KB Output is correct