Submission #136489

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
136489	2019-07-25T11:11:50 Z	imyujin	Link (CEOI06_link)	C++14	76 / 100	446 ms	37908 KB

link

#include <bits/stdc++.h>
using namespace std;

const int MAXN = 500005;

int N, K;
int A[MAXN], B[MAXN];
int ed[MAXN];
vector<int> chi[MAXN];
bool chk[MAXN], col[MAXN];
vector<int> cyc;
int nex[2 * MAXN];
int ans;

int dfs(int x) {
	//cout << "dfs(" << x << ")\n";
	chk[x] = true;
	int go = 0;
	for(auto a : chi[x]) go = max(go, dfs(a));
	if(x == 1) go = K - 1;
	else if(go-- == 0) {
		ans++;
		go = K - 1;
	}
	return go;
}

void searchgraph(int x) {
	//cout << "searchgraph(" << x << ")\n";
	for(; !chk[x]; x = ed[x]) chk[x] = true;
	for(cyc.clear(); cyc.empty() || cyc[0] != x; x = ed[x]) cyc.push_back(x);
	int go = 0;
	bool done = true;
	for(int i = 0; i < cyc.size(); i++) {
		for(auto a : chi[cyc[i]]) if(a != cyc[(i + cyc.size() - 1) % cyc.size()]) go = max(go, dfs(a));
		//cout << "go = " << go << "\n";
		if(go-- > 0) col[i] = true;
		else done = col[i] = false;
	}
	for(int i = 0; i < go; i++) col[i] = true;
	/*for(int i = 0; i < cyc.size(); i++) cout << cyc[i] << " ";
	cout << "\n";
	for(int i = 0; i < cyc.size(); i++) cout << int(col[i]) << " ";
	cout << "\n";
	cout << int(done) << "\n";*/
	if(done) return;
	if(cyc.size() <= K) {
		ans++;
		return;
	}
	for(nex[0] = K; col[nex[0] % cyc.size()]; nex[0]++);
	for(int i = 1; i < cyc.size() * 2; i++) {
		nex[i] = nex[i - 1];
		if(nex[i] < i + K) for(nex[i]++; col[nex[i] % cyc.size()]; nex[i]++);
	}
	//for(int i = 0; i < cyc.size(); i++) cout << nex[i] << " ";
	//cout << "\n";
	int mn = 0;
	for(int t = nex[0]; t < cyc.size() + nex[0]; t = nex[t]) mn++;
	for(int i = 0; i < K; i++) {
		int cnt = 0;
		for(int t = i; t < cyc.size() + i; t = nex[t]) cnt++;
		mn = min(mn, cnt);
	}
	ans += mn;
}

int main() {
	ios::sync_with_stdio(0); cin.tie(0);

	cin >> N >> K;
	for(int i = 0; i < N; i++) cin >> A[i] >> B[i];

	for(int i = 0; i < N; i++) {
		ed[A[i]] = B[i];
		chi[B[i]].push_back(A[i]);
	}

	for(int i = 1; i <= N; i++) if(!chk[i]) searchgraph(i);
	cout << ans;
	return 0;
}

Compilation message

link.cpp: In function 'void searchgraph(int)':
link.cpp:34:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 0; i < cyc.size(); i++) {
                 ~~^~~~~~~~~~~~
link.cpp:47:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  if(cyc.size() <= K) {
     ~~~~~~~~~~~^~~~
link.cpp:52:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int i = 1; i < cyc.size() * 2; i++) {
                 ~~^~~~~~~~~~~~~~~~
link.cpp:59:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for(int t = nex[0]; t < cyc.size() + nex[0]; t = nex[t]) mn++;
                      ~~^~~~~~~~~~~~~~~~~~~~~
link.cpp:62:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int t = i; t < cyc.size() + i; t = nex[t]) cnt++;
                  ~~^~~~~~~~~~~~~~~~

Subtask #1

76.0 / 100.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	12 ms	12152 KB	Output is correct
2	Incorrect	12 ms	12152 KB	Output isn't correct
3	Correct	13 ms	12152 KB	Output is correct
4	Correct	14 ms	12280 KB	Output is correct
5	Incorrect	15 ms	12380 KB	Output isn't correct
6	Correct	23 ms	13528 KB	Output is correct
7	Correct	33 ms	14584 KB	Output is correct
8	Incorrect	43 ms	15608 KB	Output isn't correct
9	Correct	66 ms	18552 KB	Output is correct
10	Correct	67 ms	17140 KB	Output is correct
11	Correct	98 ms	21488 KB	Output is correct
12	Correct	142 ms	21116 KB	Output is correct
13	Incorrect	179 ms	26104 KB	Output isn't correct
14	Correct	226 ms	26104 KB	Output is correct
15	Correct	266 ms	29940 KB	Output is correct
16	Correct	353 ms	31240 KB	Output is correct
17	Correct	347 ms	34060 KB	Output is correct
18	Incorrect	446 ms	35016 KB	Output isn't correct
19	Correct	390 ms	35316 KB	Output is correct
20	Correct	386 ms	36384 KB	Output is correct
21	Incorrect	385 ms	37908 KB	Output isn't correct
22	Correct	397 ms	36980 KB	Output is correct
23	Correct	396 ms	36592 KB	Output is correct
24	Correct	391 ms	36716 KB	Output is correct
25	Correct	391 ms	36212 KB	Output is correct