Submission #114287

#	Time	Username	Problem	Language	Result	Execution time	Memory
114287		RockyB	Unique Cities (JOI19_ho_t5)	C++17	100 / 100	819 ms	52476 KiB

joi2019_ho_t5

/// In The Name Of God

//#pragma GCC optimize("Ofast")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2,tune=native")
//#pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>

#define f first
#define s second

#define pb push_back
#define pp pop_back
#define mp make_pair

#define sz(x) (int)x.size()
#define sqr(x) ((x) * 1ll * (x))
#define all(x) x.begin(), x.end()

#define rep(i, l, r) for (int i = (l); i <= (r); i++)
#define per(i, l, r) for (int i = (l); i >= (r); i--)

#define Kazakhstan ios_base :: sync_with_stdio(0), cin.tie(0), cout.tie(0);

#define nl '\n'
#define ioi exit(0);

typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;

const int N = (int)2e5 + 7;
const int inf = (int)1e9 + 7;
const int mod = (int)1e9 + 7;
const ll linf = (ll)1e18 + 7;

const int dx[] = {-1, 0, 1, 0, 1, -1, -1, 1};
const int dy[] = {0, 1, 0, -1, 1, -1, 1, -1};

using namespace std;

int n, m;
int a[N];

vector <int> g[N];

struct S {
	int sz, df;
	int st[N], cnt[N];

	void add(int c) {
		df += cnt[c]++ == 0;
	}
	void del(int c) {
		df -= --cnt[c] == 0;
	}
	void push(int v) {
		st[++sz] = v;
		add(a[v]);
	}
	void pop() {
		del(a[st[sz--]]);
	}
	bool empty() {
		return sz == 0;
	}
	int back() {
		return st[sz];
	}
} T;

void dfs(int v, int p, vector <int> &dis) {
	dis[v] = dis[p] + 1;
	for (auto to : g[v]) {
		if (to != p) dfs(to, v, dis);
	}
}
int d[N], ans[N];
void prec(int v, int p) {
	d[v] = 1;
	for (auto to : g[v]) {
		if (to != p) {
			prec(to, v);
			d[v] = max(d[v], d[to] + 1);
		}
	}
}
void solve(int v, int p, vector <int> &dep) {
	vector < pair <int, int > > ch;
	for (auto to : g[v]) {
		if (to != p) {
			ch.pb({d[to], to});
		}
	}
	if (sz(ch)) swap(ch[0], *max_element(all(ch)));
	int len = (sz(ch) > 1) ? max_element(ch.begin() + 1, ch.end()) -> f : 0;
	if (sz(ch)) {
		for (auto to : ch) {
			while (!T.empty() && dep[T.back()] >= dep[v] - len) T.pop();
			T.push(v);
			solve(to.s, v, dep);
			if (!T.empty() && T.back() == v) T.pop();
			len = max(len, to.f);
		}
	}
	while (!T.empty() && dep[T.back()] >= dep[v] - len) T.pop();
	// if (v == 1) {
	// 	cerr << T.back() << ' ' << dep[T.back()] << ' ' << dep[v] << nl;
	// 	cerr << len << " -> " << sz(ch) << " -> " << T.sz << " -> ";
	// 	rep(i, 1, T.sz) cerr << T.st[i] << ' ';
	// 	cerr << nl;
	// }
	ans[v] = max(ans[v], T.df);
}
int main() {
	#ifdef IOI
		freopen ("in.txt", "r", stdin);
		freopen ("res.txt", "w", stdout);
	#endif
	Kazakhstan
	cin >> n >> m;
	rep(i, 2, n) {
		int v, u;
		cin >> v >> u;
		g[v].pb(u);
		g[u].pb(v);
	}
	rep(i, 1, n) {
		cin >> a[i];
	}
	vector <int> d1(n + 1);
	dfs(1, 0, d1);
	
	int A = max_element(all(d1)) - d1.begin();
	prec(A, 0);
	dfs(A, 0, d1);
	solve(A, 0, d1);

	int B = max_element(all(d1)) - d1.begin();
	prec(B, 0);
	dfs(B, 0, d1);
	solve(B, 0, d1);

	rep(i, 1, n) {
		cout << ans[i] << nl;
	}
	ioi
}

• Subtask 1: 4 / 4
• Subtask 2: 32 / 32
• Subtask 3: 32 / 32
• Subtask 4: 32 / 32