Submission #40067

#	Time	Username	Problem	Language	Result	Execution time	Memory
40067		minkank	Synchronization (JOI13_synchronization)	C++14	100 / 100	851 ms	18432 KiB

synchronization

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

typedef pair<int, int> ii;
#define st first
#define nd second

const int N = 1e5 + 5;

int n, m, q, h[N], st[N], en[N], cur, last[N], res[N], it[N * 8];
bool check[2 * N];
vector<int> G[N];
vector<ii> E;

#define mid ((l + r) / 2)

void update(int node, int l, int r, int p, int val) {
	if(p > r || p < l) return;
	if(l == r) { it[node] += val; return; }
	update(node << 1, l, mid, p, val);
	update(node << 1 | 1, mid + 1, r, p, val);
	int Left = it[node << 1], Right = it[node << 1 | 1];
	if(en[Left] > en[Right]) it[node] = Left;
	else it[node] = Right;
}

int find(int node, int l, int r, int p, int val) {
	if(p < l) return 0;
	if(r <= p && en[it[node]] < en[val]) return 0;
	if(l == r) return it[node];
	int Right = find(node << 1 | 1, mid + 1, r, p, val);
	if(Right) return Right;
	return find(node << 1, l, mid, p, val);
}

#undef mid

void dfs(int u, int p) {
	st[u] = ++cur;
	for(int v: G[u]) {
		if(v == p) continue;
		h[v] = h[u] + 1;
		dfs(v, u);
	}
	en[u] = ++cur;
}

int main() {
	//ios::sync_with_stdio(false); cin.tie(0);
	cin >> n >> m >> q;
	for(int i = 1; i < n; ++i) {
		int u, v;
		cin >> u >> v;
		G[u].push_back(v);
		G[v].push_back(u);
		E.push_back(ii(u, v));
	}
	dfs(1, 1);
	for(int i = 1; i <= n; ++i) res[i] = 1, update(1, 1, 2 * n, st[i], i);
	for(int i = 1; i <= m; ++i) {
		int id;
		cin >> id; id--;
		int u, v;
		u = E[id].st; v = E[id].nd;
		if(h[u] > h[v]) swap(u, v);
		int p = find(1, 1, 2 * n, st[u], u);
		if(!check[id]) {
			res[p] += res[v] - last[v];
			update(1, 1, 2 * n, st[v], -v);
		}
		else {
			res[v] = res[p];
			update(1, 1, 2 * n, st[v], v);
		}
		last[v] = res[v];
		check[id] ^= 1;
	}
	for(int i = 1; i <= q; ++i) {
		int u;
		cin >> u;
		cout << res[find(1, 1, 2 * n, st[u], u)] << '\n';
	}
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 10 / 10
• Subtask 4: 20 / 20
• Subtask 5: 40 / 40