Submission #100888

#	Time	Username	Problem	Language	Result	Execution time	Memory
100888		square1001	Synchronization (JOI13_synchronization)	C++14	30 / 100	8071 ms	24484 KiB

synchronization

#include <vector>
#include <iostream>
#include <algorithm>
#include <functional>
using namespace std;
vector<int> solve_30pts(int N, int M, int Q, vector<int> X, vector<int> Y, vector<int> seq, vector<int> query) {
	vector<int> ans(Q);
	vector<int> par(N);
	vector<vector<int> > G(N);
	for(int i = 0; i < N - 1; ++i) {
		G[X[i]].push_back(Y[i]);
		G[Y[i]].push_back(X[i]);
	}
	function<void(int, int)> dfs = [&](int pos, int pre) {
		par[pos] = pre;
		for(int i : G[pos]) {
			if(i != pre) dfs(i, pos);
		}
	};
	vector<vector<int> > g(N - 1);
	for(int i = 0; i < M; ++i) {
		g[seq[i]].push_back(i);
	}
	for(int i = 0; i < Q; ++i) {
		dfs(query[i], -1);
		vector<int> pindex(N, -1);
		for(int j = 0; j < N - 1; ++j) {
			if(par[X[j]] == Y[j]) pindex[X[j]] = j;
			else pindex[Y[j]] = j;
		}
		function<int(int, int, int)> calc = [&](int pos, int pre, int timing) {
			int ans = 1;
			for(int i : G[pos]) {
				if(i == pre) continue;
				int ptr = lower_bound(g[pindex[i]].begin(), g[pindex[i]].end(), timing) - g[pindex[i]].begin();
				if(ptr % 2 == 1) ans += calc(i, pos, timing);
				else if(ptr != 0) ans += calc(i, pos, g[pindex[i]][ptr - 1]);
			}
			return ans;
		};
		ans[i] = calc(query[i], -1, M);
	}
	return ans;
}
int main() {
	cin.tie(0);
	ios_base::sync_with_stdio(false);
	int N, M, Q;
	cin >> N >> M >> Q;
	vector<int> X(N - 1), Y(N - 1), seq(M), query(Q);
	for(int i = 0; i < N - 1; ++i) {
		cin >> X[i] >> Y[i]; --X[i],--Y[i];
	}
	for(int i = 0; i < M; ++i) {
		cin >> seq[i]; --seq[i];
	}
	for(int i = 0; i < Q; ++i) {
		cin >> query[i]; --query[i];
	}
	vector<int> ans = solve_30pts(N, M, Q, X, Y, seq, query);
	for(int i : ans) {
		cout << i << '\n';
	}
	return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 20 / 20
• Subtask 3: 0 / 10
• Subtask 4: 0 / 20
• Subtask 5: 0 / 40