oj.uz

Submission #350351

# Submission time Handle Problem Language Result Execution time Memory
350351 2021-01-19T05:13:00 Z Kevin_Zhang_TW Parachute rings (IOI12_rings) C++17
55 / 100
 4000 ms 224648 KB 
#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define pb emplace_back
#define AI(i) begin(i), end(i)
template<class T> bool chmin(T &a, T b) { return b < a && (a = b, true); }
template<class T> bool chmax(T &a, T b) { return a < b && (a = b, true); }
#ifdef KEV
#define DE(args...) kout("[ " + string(#args) + " ] = ", args)
void kout() { cerr << endl; }
template<class T, class ...U> void kout(T a, U ...b) { cerr << a << ' ', kout(b...); }
template<class T> void debug(T L, T R) { while (L != R) cerr << *L << " \n"[next(L) == R], ++L; }
#else
#define DE(...) 0
#define debug(...) 0
#endif

const int MAX_N = 1000005;

int N, glob;

struct dsu {
	vector<int> g, sz, deg;

	int n, badcnt, allbad, answer;

	dsu() {};
	dsu (int n, int size) : n(n), answer(size), badcnt(0), allbad(0) { 
		deg = g = vector<int>(n);
		sz = vector<int>(n, 1);
		iota(AI(g), 0); 
	}

	int F(int i) { return i == g[i] ? i : g[i] = F(g[i]); }

	void M(int a, int b) { 

		if (max(++deg[a], ++deg[b]) >= 3) allbad = true;

		if (allbad) return;

		a = F(a), b = F(b);
		if (sz[a] < sz[b]) swap(a, b);

		if (a != b) {
			return sz[a] += sz[b], g[b] = a, void();
		}
		if (++badcnt == 2) allbad = true;
		// merging into a ring
		// which means you have to remove objects on the ring
		// all of them is ok, since max deg is 2
		// I only care when max deg is <= 2
		// and a ring cannot merge with other for max deg <= 2
		answer = sz[a];
	}
	bool noring() { return badcnt == 0 && allbad == false; }

	int getans() { 
		return allbad ? 0 : answer;
	}
};

dsu alld, forone;

vector<int> edge[MAX_N];

bool iscan[MAX_N];

vector<int> big, can;

vector<dsu> forcan;

void canpush(int id) { if (iscan[id]) return; iscan[id] = true, can.pb(id); }

void Init(int N_) {
	N = N_;
	glob = N;
	alld = dsu(N, N);
}

vector<pair<int,int>> alledge;
// TODO big crisis
// new edge is {a, b}
int over = -1;

void superbig(int id) {
	if (over == -1) {
		over = id;
		forone = dsu(N, N-1);
		for (auto [a, b] : alledge)
			if (a != id && b != id)
				forone.M(a, b);
		glob = forone.noring();
	}
	else if (over != id) {
		glob = -1;
		return;
	}
	else {
		auto [a, b] = alledge.back();
		if (a != id && b != id)
			forone.M(a, b);
		glob = forone.noring();
	}
}
void adjust(int a, int b) {
	if (glob == -1) return;

	DE(a, b);

	if (big.empty()) {
		assert(can.empty());

		alld.M(a, b);

		glob = alld.getans();

		return;
	}

 	// deal with old ones
 	int oldsize = can.size();
 	for (int i = 0;i < oldsize;++i) {
 		int x = can[i];
 		if (a != x && b != x)
 			forcan[i].M(a, b);
 	}
 
	// put new element into candidate
	for (int x : big) {
		// assert(edge[x].size() <= 3);
		canpush(x);
		for (int u : edge[x]) canpush(u);
	}
	// examine new candidates
 
 	for (int i = oldsize;i < can.size();++i) {
 		forcan.pb(N, N-1);
 		int x = can[i];
 		for (auto [a, b] : alledge) if (a != x && b != x) {
 			forcan[i].M(a, b);
 		}
 	}

	// assert(forcan.size() == can.size());

	glob = 0;

 	// examine all candidates
 	for (int i = 0;i < can.size();++i) 
 		glob += forcan[i].noring();

}
void Link(int A, int B) {
	if (glob == -1) return;

	edge[A].pb(B), edge[B].pb(A);

	if (edge[A].size() == 3) big.pb(A);
	if (edge[B].size() == 3) big.pb(B);

	alledge.pb(A, B);

 	if (edge[A].size() > 3) superbig(A);
 	if (edge[B].size() > 3) superbig(B);


// 	if (over != -1) {
// 	   superbig(over);
// 	   return;
// 	}
	if (over != -1) return;

 	if (big.size() > 4) {
 		glob = -1;
 		return;
 	}
	
	adjust(A, B);
}

int CountCritical() {
	if (over != -1) {
		dsu now(N, N-1);
		for (auto [a, b] : alledge)
			if (a != over && b != over)
				now.M(a, b);
		return now.noring();
	}
	return max(glob, 0);
}

Compilation message

rings.cpp: In constructor 'dsu::dsu(int, int)':
rings.cpp:25:25: warning: 'dsu::answer' will be initialized after [-Wreorder]
   25 |  int n, badcnt, allbad, answer;
      |                         ^~~~~~
rings.cpp:25:9: warning:   'int dsu::badcnt' [-Wreorder]
   25 |  int n, badcnt, allbad, answer;
      |         ^~~~~~
rings.cpp:28:2: warning:   when initialized here [-Wreorder]
   28 |  dsu (int n, int size) : n(n), answer(size), badcnt(0), allbad(0) {
      |  ^~~
rings.cpp: In function 'void adjust(int, int)':
rings.cpp:14:17: warning: statement has no effect [-Wunused-value]
   14 | #define DE(...) 0
      |                 ^
rings.cpp:109:2: note: in expansion of macro 'DE'
  109 |  DE(a, b);
      |  ^~
rings.cpp:137:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  137 |   for (int i = oldsize;i < can.size();++i) {
      |                        ~~^~~~~~~~~~~~
rings.cpp:150:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  150 |   for (int i = 0;i < can.size();++i)
      |                  ~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23788 KB Output is correct
2 Correct 19 ms 24300 KB Output is correct
3 Correct 19 ms 24428 KB Output is correct
4 Correct 17 ms 23916 KB Output is correct
5 Correct 18 ms 24044 KB Output is correct
6 Correct 19 ms 24172 KB Output is correct
7 Correct 17 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 20 ms 24428 KB Output is correct
10 Correct 21 ms 24556 KB Output is correct

Subtask #2
17.0 / 17.0

# Verdict Execution time Memory Grader output
1 Correct 545 ms 50260 KB Output is correct
2 Correct 1209 ms 120984 KB Output is correct
3 Correct 406 ms 201576 KB Output is correct
4 Correct 1291 ms 74696 KB Output is correct
5 Correct 1296 ms 74732 KB Output is correct
6 Correct 1270 ms 73328 KB Output is correct
7 Correct 462 ms 224648 KB Output is correct
8 Correct 2143 ms 137344 KB Output is correct
9 Correct 2411 ms 156768 KB Output is correct
10 Correct 901 ms 72516 KB Output is correct

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23788 KB Output is correct
2 Correct 19 ms 24300 KB Output is correct
3 Correct 19 ms 24428 KB Output is correct
4 Correct 17 ms 23916 KB Output is correct
5 Correct 18 ms 24044 KB Output is correct
6 Correct 19 ms 24172 KB Output is correct
7 Correct 17 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 20 ms 24428 KB Output is correct
10 Correct 21 ms 24556 KB Output is correct
11 Correct 20 ms 24428 KB Output is correct
12 Correct 27 ms 25836 KB Output is correct
13 Correct 29 ms 25580 KB Output is correct
14 Correct 27 ms 24940 KB Output is correct
15 Correct 32 ms 25800 KB Output is correct
16 Correct 28 ms 24428 KB Output is correct
17 Correct 21 ms 25836 KB Output is correct
18 Correct 26 ms 27884 KB Output is correct
19 Correct 23 ms 24428 KB Output is correct
20 Correct 23 ms 25196 KB Output is correct

Subtask #4
0 / 14.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23788 KB Output is correct
2 Correct 19 ms 24300 KB Output is correct
3 Correct 19 ms 24428 KB Output is correct
4 Correct 17 ms 23916 KB Output is correct
5 Correct 18 ms 24044 KB Output is correct
6 Correct 19 ms 24172 KB Output is correct
7 Correct 17 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 20 ms 24428 KB Output is correct
10 Correct 21 ms 24556 KB Output is correct
11 Correct 20 ms 24428 KB Output is correct
12 Correct 27 ms 25836 KB Output is correct
13 Correct 29 ms 25580 KB Output is correct
14 Correct 27 ms 24940 KB Output is correct
15 Correct 32 ms 25800 KB Output is correct
16 Correct 28 ms 24428 KB Output is correct
17 Correct 21 ms 25836 KB Output is correct
18 Correct 26 ms 27884 KB Output is correct
19 Correct 23 ms 24428 KB Output is correct
20 Correct 23 ms 25196 KB Output is correct
21 Correct 45 ms 25704 KB Output is correct
22 Correct 57 ms 26724 KB Output is correct
23 Correct 75 ms 27492 KB Output is correct
24 Execution timed out 4025 ms 32240 KB Time limit exceeded
25 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 16 ms 23788 KB Output is correct
2 Correct 19 ms 24300 KB Output is correct
3 Correct 19 ms 24428 KB Output is correct
4 Correct 17 ms 23916 KB Output is correct
5 Correct 18 ms 24044 KB Output is correct
6 Correct 19 ms 24172 KB Output is correct
7 Correct 17 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 20 ms 24428 KB Output is correct
10 Correct 21 ms 24556 KB Output is correct
11 Correct 545 ms 50260 KB Output is correct
12 Correct 1209 ms 120984 KB Output is correct
13 Correct 406 ms 201576 KB Output is correct
14 Correct 1291 ms 74696 KB Output is correct
15 Correct 1296 ms 74732 KB Output is correct
16 Correct 1270 ms 73328 KB Output is correct
17 Correct 462 ms 224648 KB Output is correct
18 Correct 2143 ms 137344 KB Output is correct
19 Correct 2411 ms 156768 KB Output is correct
20 Correct 901 ms 72516 KB Output is correct
21 Correct 20 ms 24428 KB Output is correct
22 Correct 27 ms 25836 KB Output is correct
23 Correct 29 ms 25580 KB Output is correct
24 Correct 27 ms 24940 KB Output is correct
25 Correct 32 ms 25800 KB Output is correct
26 Correct 28 ms 24428 KB Output is correct
27 Correct 21 ms 25836 KB Output is correct
28 Correct 26 ms 27884 KB Output is correct
29 Correct 23 ms 24428 KB Output is correct
30 Correct 23 ms 25196 KB Output is correct
31 Correct 45 ms 25704 KB Output is correct
32 Correct 57 ms 26724 KB Output is correct
33 Correct 75 ms 27492 KB Output is correct
34 Execution timed out 4025 ms 32240 KB Time limit exceeded
35 Halted 0 ms 0 KB -