oj.uz

Submission #350349

# Submission time Handle Problem Language Result Execution time Memory
350349 2021-01-19T05:12:28 Z Kevin_Zhang_TW Parachute rings (IOI12_rings) C++17
38 / 100
 69 ms 60780 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);
	assert(N <= 20000);
// 	for (int i = 0;i < N;++i)
// 		adsu[i] = dsu(N, N-1);
}

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:112:2: note: in expansion of macro 'DE'
  112 |  DE(a, b);
      |  ^~
rings.cpp:140:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  140 |   for (int i = oldsize;i < can.size();++i) {
      |                        ~~^~~~~~~~~~~~
rings.cpp:153:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  153 |   for (int i = 0;i < can.size();++i)
      |                  ~~^~~~~~~~~~~~

Subtask #1
20.0 / 20.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23788 KB Output is correct
2 Correct 20 ms 24300 KB Output is correct
3 Correct 22 ms 24428 KB Output is correct
4 Correct 19 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 18 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 19 ms 24428 KB Output is correct
10 Correct 22 ms 24556 KB Output is correct

Subtask #2
0 / 17.0

# Verdict Execution time Memory Grader output
1 Runtime error 69 ms 60780 KB Execution killed with signal 6 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #3
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23788 KB Output is correct
2 Correct 20 ms 24300 KB Output is correct
3 Correct 22 ms 24428 KB Output is correct
4 Correct 19 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 18 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 19 ms 24428 KB Output is correct
10 Correct 22 ms 24556 KB Output is correct
11 Correct 20 ms 24428 KB Output is correct
12 Correct 25 ms 25736 KB Output is correct
13 Correct 26 ms 25580 KB Output is correct
14 Correct 29 ms 24940 KB Output is correct
15 Correct 33 ms 25800 KB Output is correct
16 Correct 21 ms 24428 KB Output is correct
17 Correct 25 ms 25964 KB Output is correct
18 Correct 22 ms 27884 KB Output is correct
19 Correct 24 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 17 ms 23788 KB Output is correct
2 Correct 20 ms 24300 KB Output is correct
3 Correct 22 ms 24428 KB Output is correct
4 Correct 19 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 18 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 19 ms 24428 KB Output is correct
10 Correct 22 ms 24556 KB Output is correct
11 Correct 20 ms 24428 KB Output is correct
12 Correct 25 ms 25736 KB Output is correct
13 Correct 26 ms 25580 KB Output is correct
14 Correct 29 ms 24940 KB Output is correct
15 Correct 33 ms 25800 KB Output is correct
16 Correct 21 ms 24428 KB Output is correct
17 Correct 25 ms 25964 KB Output is correct
18 Correct 22 ms 27884 KB Output is correct
19 Correct 24 ms 24428 KB Output is correct
20 Correct 23 ms 25196 KB Output is correct
21 Runtime error 56 ms 49388 KB Execution killed with signal 6 (could be triggered by violating memory limits)
22 Halted 0 ms 0 KB -

Subtask #5
0 / 31.0

# Verdict Execution time Memory Grader output
1 Correct 17 ms 23788 KB Output is correct
2 Correct 20 ms 24300 KB Output is correct
3 Correct 22 ms 24428 KB Output is correct
4 Correct 19 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 18 ms 24812 KB Output is correct
8 Correct 18 ms 24044 KB Output is correct
9 Correct 19 ms 24428 KB Output is correct
10 Correct 22 ms 24556 KB Output is correct
11 Runtime error 69 ms 60780 KB Execution killed with signal 6 (could be triggered by violating memory limits)
12 Halted 0 ms 0 KB -