Submission #376844

# Submission time Handle Problem Language Result Execution time Memory
376844 2021-03-12T05:19:40 Z Kevin_Zhang_TW Mergers (JOI19_mergers) C++17
0 / 100
91 ms 40932 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 = 500010, MAX_K = 20;

int n, k, belong[MAX_N];
vector<int> edge[MAX_N];
vector<int> state[MAX_N];
ll sum[MAX_N];

int anc[MAX_K][MAX_N], in[MAX_N], out[MAX_N];
bool isanc(int a, int b) { return in[a] <= in[b] && out[a] >= out[b]; }
void dfs(int x, int lst = 1) {
	static int t;
	anc[0][x] = lst;
	in[x] = ++t;
	for (int u : edge[x]) if (u != lst)
		dfs(u, x);
	out[x] = t;
}

void dfs2(int x, int lst = -1) {
	for (int u : edge[x]) if (u != lst) {
		dfs2(u, x);
		sum[x] += sum[u];
	}
}

int dp[MAX_N], res;

int dfs3(int x, int lst = -1) {
	int son = 0;
	for (int u : edge[x]) if (u != lst)
		son += dfs3(u, x);

	if (son == 0 && sum[x] == 0 && lst != -1) {
		++son;
		DE(x);
	}

	chmax(res, son);

	if (lst != -1 && sum[x] == 0) {
		chmax(res, son + 1);
	}

	return dp[x] = son;
}
int getlca(int a, int b) {
	for (int d = MAX_K-1;d >= 0;--d)
		if (!isanc(anc[d][a], b))
			a = anc[d][a];
	return isanc(a, b) ? a : anc[0][a];
}

int32_t main() {
	ios_base::sync_with_stdio(0), cin.tie(0);
	cin >> n >> k;
	for (int a, b, i = 1;i < n;++i) {
		cin >> a >> b;
		edge[a].pb(b), edge[b].pb(a);
	}
	for (int i = 1;i <= n;++i) {
		cin >> belong[i];
		state[ belong[i] ].pb(i);
	}
	int rt = 1;
	while (edge[rt].size() > 1) ++rt;

	if (k == 1) return cout << 0 << '\n', 0;


	dfs(rt);
	for (int d = 1;d < MAX_K;++d)
		for (int i = 1;i <= n;++i)
			anc[d][i] = anc[d-1][ anc[d-1][i] ];

	for (int i = 1;i <= k;++i) {
		if (state[i].size() > 1) {
			sort(AI(state[i]), [&](int a, int b) {
					return in[a] < in[b];
					});
			for (int x : state[i])
				++sum[x];
			sum[ getlca(state[i][0], state[i].back()) ] -= state[i].size();
		}
	}

	dfs2(rt);

	dfs3(rt);
	res = (res+1) / 2;
	cout << res << '\n';
}

Compilation message

mergers.cpp: In function 'int dfs3(int, int)':
mergers.cpp:14:17: warning: statement has no effect [-Wunused-value]
   14 | #define DE(...) 0
      |                 ^
mergers.cpp:51:3: note: in expansion of macro 'DE'
   51 |   DE(x);
      |   ^~
# Verdict Execution time Memory Grader output
1 Correct 17 ms 24044 KB Output is correct
2 Correct 17 ms 24044 KB Output is correct
3 Correct 17 ms 24044 KB Output is correct
4 Correct 17 ms 24044 KB Output is correct
5 Correct 17 ms 24044 KB Output is correct
6 Correct 17 ms 23788 KB Output is correct
7 Correct 17 ms 23788 KB Output is correct
8 Correct 17 ms 24044 KB Output is correct
9 Correct 17 ms 24044 KB Output is correct
10 Correct 17 ms 24044 KB Output is correct
11 Correct 17 ms 24044 KB Output is correct
12 Correct 17 ms 24044 KB Output is correct
13 Correct 17 ms 24044 KB Output is correct
14 Incorrect 17 ms 24044 KB Output isn't correct
15 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 17 ms 24044 KB Output is correct
2 Correct 17 ms 24044 KB Output is correct
3 Correct 17 ms 24044 KB Output is correct
4 Correct 17 ms 24044 KB Output is correct
5 Correct 17 ms 24044 KB Output is correct
6 Correct 17 ms 23788 KB Output is correct
7 Correct 17 ms 23788 KB Output is correct
8 Correct 17 ms 24044 KB Output is correct
9 Correct 17 ms 24044 KB Output is correct
10 Correct 17 ms 24044 KB Output is correct
11 Correct 17 ms 24044 KB Output is correct
12 Correct 17 ms 24044 KB Output is correct
13 Correct 17 ms 24044 KB Output is correct
14 Incorrect 17 ms 24044 KB Output isn't correct
15 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 17 ms 24044 KB Output is correct
2 Correct 17 ms 24044 KB Output is correct
3 Correct 17 ms 24044 KB Output is correct
4 Correct 17 ms 24044 KB Output is correct
5 Correct 17 ms 24044 KB Output is correct
6 Correct 17 ms 23788 KB Output is correct
7 Correct 17 ms 23788 KB Output is correct
8 Correct 17 ms 24044 KB Output is correct
9 Correct 17 ms 24044 KB Output is correct
10 Correct 17 ms 24044 KB Output is correct
11 Correct 17 ms 24044 KB Output is correct
12 Correct 17 ms 24044 KB Output is correct
13 Correct 17 ms 24044 KB Output is correct
14 Incorrect 17 ms 24044 KB Output isn't correct
15 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 82 ms 39012 KB Output is correct
2 Correct 91 ms 40932 KB Output is correct
3 Incorrect 19 ms 24556 KB Output isn't correct
4 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 17 ms 24044 KB Output is correct
2 Correct 17 ms 24044 KB Output is correct
3 Correct 17 ms 24044 KB Output is correct
4 Correct 17 ms 24044 KB Output is correct
5 Correct 17 ms 24044 KB Output is correct
6 Correct 17 ms 23788 KB Output is correct
7 Correct 17 ms 23788 KB Output is correct
8 Correct 17 ms 24044 KB Output is correct
9 Correct 17 ms 24044 KB Output is correct
10 Correct 17 ms 24044 KB Output is correct
11 Correct 17 ms 24044 KB Output is correct
12 Correct 17 ms 24044 KB Output is correct
13 Correct 17 ms 24044 KB Output is correct
14 Incorrect 17 ms 24044 KB Output isn't correct
15 Halted 0 ms 0 KB -