Submission #285808

#	Time	Username	Problem	Language	Result	Execution time	Memory
285808		Saboon	Friend (IOI14_friend)	C++14	69 / 100	39 ms	3320 KiB

friend

#include "friend.h"
#include<bits/stdc++.h>
using namespace std;
const int maxn = 5050;
const int inf = 1e9;

int n, pd[maxn], V[maxn], dp[maxn], c[maxn], a[maxn], type[maxn];
vector<int> t[maxn];
int par[maxn], adj[maxn];

int dfs(int v){
	if (type[v] == 1){
		int lc = t[v][0], rc = t[v][1];
		dfs(lc);
		dfs(rc);
		dp[v] = dp[lc]+pd[rc];
		pd[v] = pd[lc]+dp[rc];
		dp[v] = max(dp[v],pd[v]);
	}
	else{
		dp[v] = c[v];
		for (auto u : t[v]){
			dfs(u);
			dp[v] += dp[u];
			pd[v] += pd[u];
		}
		dp[v] = max(dp[v],pd[v]);
	}
	return dp[v];
}

void addEdge(int v, int u){
	t[v].push_back(u);
	par[u] = v;
}

int findSample(int N,int confidence[],int host[],int protocol[]){
	n = N;
	if (n <= 10){
		for (int i = 0; i < n; i++)
			adj[i] = (1 << i);
		for (int i = 1; i < n; i++){
			if (protocol[i] == 0)
				adj[host[i]] |= (1 << i), adj[i] |= (1 << host[i]);
			else
				for (int j = 0; j < n; j++)
					if (adj[host[i]] & (1 << j) and j != host[i])
						adj[j] |= (1 << i), adj[i] |= (1 << j);
			if (protocol[i] == 2)
				adj[host[i]] |= (1 << i), adj[i] |= (1 << host[i]);
		}
		dp[0] = 0;
		for (int mask = 1; mask < (1 << n); mask++){
			dp[mask] = -inf;
			for (int i = 0; i < n; i++){
				if (mask & (1 << i)){
					int sub = (mask & (adj[i]|(1<<i)));
					dp[mask] = dp[mask^sub] + confidence[i];
				}
			}
		}
		return *max_element(dp, dp+(1<<n));
	}
	if (*min_element(protocol+1, protocol+n) == 2 and *max_element(protocol+1, protocol+n) == 2)
		return *max_element(confidence, confidence+n);
	int newint = n+1;
	addEdge(0, 1);
	V[0] = 1;
	c[1] = confidence[0];
	for (int i = 1; i < n; i++){
		int v = V[host[i]];
		if (protocol[i] == 0){
			c[V[host[i]]] = 0;
			type[v] = 1;
			addEdge(v, newint++);
			addEdge(newint-1, newint);
			V[host[i]] = newint++;
			addEdge(v, newint++);
			addEdge(newint-1, newint);
			V[i] = newint++;
			c[V[i]] = confidence[i];
			c[V[host[i]]] = confidence[host[i]];
		}
		else{
			addEdge(par[v], newint++);
			V[i] = newint-1;
			c[V[i]] = confidence[i];
		}
	}
	return dfs(0);
}

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