Submission #129507

#	Time	Username	Problem	Language	Result	Execution time	Memory
129507		antimirage	Friend (IOI14_friend)	C++14	0 / 100	8 ms	5368 KiB

friend

#include "friend.h"
//#include "grader.cpp"
#include <bits/stdc++.h>

#define fr first
#define sc second
#define mk make_pair
#define pb push_back
#define all(s) s.begin(), s.end()

using namespace std;

const int N = 1e5 + 5;

vector <int> g[N], vec;

int u[N], dp[N][2], ans;

int bfs (int v) {
	
	int start = v;
	
	vec.clear();
	queue <int> q;
	q.push(v);
	u[v] = 1;
	
	while (!q.empty() ) {
		v = q.front();
		q.pop();
		vec.pb(v);
		for (auto to : g[v]) {
			if (u[to]) continue;
			u[to] = u[v] + 1;
			q.push(to);
		}
	}
	reverse(all(vec));
	
	for (auto it : vec) {
		v = it;
		for (auto to : g[v]) {
			if (u[to] > u[v]) {
				assert(u[to] - 1 == u[v]);
				dp[v][1] += dp[to][0];
				dp[v][0] += max(dp[to][1], dp[to][0]);
			}
		}
	}
	return max(dp[start][0], dp[start][1]);
}

int findSample(int n, int val[], int batya[], int type[]) {
	
	assert(val[0] == 1);
	dp[0][1] = 1;
	for (int i = 1; i < n; i++) {
		dp[i][1] = 1;
		assert(val[i] == 1);
		
		if (type[i] == 0) {
			g[batya[i]].pb(i);
			g[i].pb(batya[i]);
		}
		else if (type[i] == 1) {
			for (auto it: g[batya[i]]) {
				g[i].pb(it);
				g[it].pb(i);
			}
		}
		else
			assert(0);
	}
	for (int i = 0; i < n; i++) {
		if (u[i]) continue;
		ans += bfs(i);
	}
	return ans;
}

• Subtask 1: 0 / 11
• Subtask 2: 0 / 8
• Subtask 3: 0 / 8
• Subtask 4: 0 / 19
• Subtask 5: 0 / 23
• Subtask 6: 0 / 31