Submission #136485

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
136485	2019-07-25T11:08:32 Z	imyujin	Link (CEOI06_link)	C++14	76 / 100	445 ms	37876 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[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	12064 KB	Output is correct
2	Incorrect	15 ms	12156 KB	Output isn't correct
3	Correct	14 ms	12152 KB	Output is correct
4	Correct	14 ms	12252 KB	Output is correct
5	Incorrect	14 ms	12280 KB	Output isn't correct
6	Correct	25 ms	13508 KB	Output is correct
7	Correct	32 ms	14460 KB	Output is correct
8	Incorrect	43 ms	15580 KB	Output isn't correct
9	Correct	60 ms	18552 KB	Output is correct
10	Correct	60 ms	17124 KB	Output is correct
11	Correct	99 ms	21404 KB	Output is correct
12	Correct	138 ms	21136 KB	Output is correct
13	Incorrect	181 ms	26104 KB	Output isn't correct
14	Correct	223 ms	26020 KB	Output is correct
15	Correct	254 ms	29740 KB	Output is correct
16	Correct	306 ms	31216 KB	Output is correct
17	Correct	335 ms	34032 KB	Output is correct
18	Incorrect	374 ms	35100 KB	Output isn't correct
19	Correct	374 ms	35404 KB	Output is correct
20	Correct	374 ms	36420 KB	Output is correct
21	Incorrect	383 ms	37876 KB	Output isn't correct
22	Correct	389 ms	36840 KB	Output is correct
23	Correct	370 ms	36720 KB	Output is correct
24	Correct	386 ms	36596 KB	Output is correct
25	Correct	445 ms	36340 KB	Output is correct