Submission #350199

# Submission time Handle Problem Language Result Execution time Memory
350199 2021-01-19T04:11:46 Z Kevin_Zhang_TW Parachute rings (IOI12_rings) C++17
0 / 100
1714 ms 262148 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) { 
		g.resize(n);
		sz.resize(n, 1);
		deg.resize(n);
		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
		answer = sz[a];

	}

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

dsu adsu[20010];

dsu alld;

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);
	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}
void adjust(int a, int b) {
	DE(a, b);
	if (glob == -1) return;

	if (big.empty()) {
		alld.M(a, b);
		glob = alld.getans();
		alledge.pb(a, b);
		return;
	}

	glob = 0;

	int oldsize = forcan.size();
	// put new element into candidate
	for (int x : big) {
		canpush(x);
		for (int u : edge[x]) canpush(u);
	}
	// cerr << "a lot of candidate\n";
	// debug(AI(can));

	// 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);
		}
	}

	// examine all candidates
	for (int i = 0;i < can.size();++i) {
		int x = can[i];
		if (a != x && b != x)
			forcan[i].M(a, b);
		// DE(x, forcan[i].getans(), N-1);
		glob += forcan[i].getans() == N - 1;
	}

	alledge.pb(a, b);
}
void Link(int A, int B) {


	for (int i = 0;i < N;++i) if (i != A && i != B)
		adsu[i].M(A, B);
	return;


	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);
	if (big.size() > 3) {
		glob = -1;
		return;
	}
	adjust(A, B);
}

int CountCritical() {
	int res = 0;
	for (int i = 0;i < N;++i)
		if (adsu[i].getans() == N - 1) ++res;
	return res;
	return max(0, glob);
}

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:86:2: note: in expansion of macro 'DE'
   86 |  DE(a, b);
      |  ^~
rings.cpp:109:25: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  109 |  for (int i = oldsize;i < can.size();++i) {
      |                       ~~^~~~~~~~~~~~
rings.cpp:118:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  118 |  for (int i = 0;i < can.size();++i) {
      |                 ~~^~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 18 ms 25708 KB Output is correct
2 Correct 1714 ms 231532 KB Output is correct
3 Runtime error 177 ms 262144 KB Execution killed with signal 9 (could be triggered by violating memory limits)
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Runtime error 185 ms 262148 KB Execution killed with signal 9 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 18 ms 25708 KB Output is correct
2 Correct 1714 ms 231532 KB Output is correct
3 Runtime error 177 ms 262144 KB Execution killed with signal 9 (could be triggered by violating memory limits)
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 18 ms 25708 KB Output is correct
2 Correct 1714 ms 231532 KB Output is correct
3 Runtime error 177 ms 262144 KB Execution killed with signal 9 (could be triggered by violating memory limits)
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 18 ms 25708 KB Output is correct
2 Correct 1714 ms 231532 KB Output is correct
3 Runtime error 177 ms 262144 KB Execution killed with signal 9 (could be triggered by violating memory limits)
4 Halted 0 ms 0 KB -