Submission #586402

#	Time	Username	Problem	Language	Result	Execution time	Memory
586402		LastRonin	Friend (IOI14_friend)	C++14	46 / 100	25 ms	2872 KiB

friend

#include "friend.h"
#include <bits/stdc++.h>
#define ll long long
#define pb push_back
using namespace std;

const ll N = 1e3 + 10;

vector<ll> g[N];
ll dp[N][2];
bool was[N]; 
ll we[N];

void dfs(ll v, ll p) {
	was[v] = 1;
	for(auto u : g[v]) {
		if(u != p) {
			dfs(u, v);
			dp[v][0] += max(dp[u][0], dp[u][1]);
			dp[v][1] += dp[u][0];
		}
	}
	dp[v][1] += we[v]; 
}


ll col[N];
vector<int> comp;

void dfs2(ll v, ll a) {
	comp.pb(v);
	col[v] = a;
	was[v] = 1;		
	for(auto u : g[v]) {
		if(!was[u]) {
			dfs2(u, a^3);
		}
		assert(col[v] != col[u]);
	}
}


int findSample(int n,int confidence[],int host[],int protocol[]){
    bool eq = 1;
    for(int j = 0; j < n; j++)
    	we[j] = confidence[j];
    for(int j = 1; j < n - 1; j++) {
		if(protocol[j] != protocol[j + 1])
			eq = 0;						
    }
    if(eq) {
    	if(protocol[1] == 1) {
			// empty
			ll sum = 0;
			for(int j = 0; j < n; j++)
				sum += confidence[j];
			return sum;
    	} else if(protocol[1] == 2) {
			// full
			ll mx = 0;
			for(int j = 0; j < n; j++)
				mx = max(mx, (ll)confidence[j]);
			return mx;
    	} else if(protocol[1] == 0) {
    		// tree
    		for(int j = 1; j < n; j++) {
				g[host[j]].pb(j);
				g[j].pb(host[j]);
    		}
    		ll ans = 0;
			for(int i = 0; i < n; i++) {
				if(!was[i]) {
					dfs(i, -1);				    	
					ans += max(dp[i][1], dp[i][0]);
				}
	    	}
	    	return ans;
    	}
    } else {
    	for(int j = 1; j < n; j++) {
			if(protocol[j] == 0) {
				g[j].pb(host[j]);
				g[host[j]].pb(j);
			} else if(protocol[j] == 1) {
				for(auto u : g[host[j]]) {
					g[j].pb(u);
					g[u].pb(j);
				}
            } else if(protocol[j] == 2) {
				for(auto u : g[host[j]]) {
					g[j].pb(u);
					g[u].pb(j);
				}
				g[j].pb(host[j]);
				g[host[j]].pb(j);            	
            }
    	}
    	if(n <= 10) {
    		ll mx = 0;
			for(int j = 0; j < (1<<n); j++) {
				bool incor = 0;			
				ll sum = 0;
				for(int i = 0; i < n; i++) {
					if((1<<i)&j)
						sum = sum + confidence[i]; 					
				}
				for(int i = 0; i < n; i++) {
					if((1<<i)&j) {
						for(auto u : g[i])
							if((1<<u)&j)
								incor = 1;
					}
				}
				if(incor == 0)
					mx = max(mx, sum);
			}
			return mx;
		} else {
			ll answ = 0;
			for(int i = 0; i < n; i++)
				comp.clear(), was[i] = 0, assert(we[i] == 1);
			for(int i = 0; i < n; i++) {
				if(!was[i]) {
					comp.clear();
					dfs2(i, 1);
					ll kek = 0;
					ll kek2 = 0;
					for(auto u : comp) {
						if(col[u] == 1)kek++;
						else if(col[u] == 2)kek2++;
						else assert(0);
				 	}
				 	answ += max(kek, kek2);
				 	comp.clear();
				}
			}
			return answ;
		}
	}
	return 0;
}
/*
6
13 3 6 20 10 15
0 0 0 1 1 2 2 1 0 0
6
13 3 6 20 10 15
0 0 0 1 1 2 2 1 0 0

*/
/*
#define __MAXSIZE__ 100002
#include "friend.h"
using namespace std;

// Confidence
int confidence[__MAXSIZE__];

// Host
int host[__MAXSIZE__];

// Protocol
int protocol[__MAXSIZE__];

// Main
int main(void)
{
	int n,i;

	// Number of people
	assert(scanf("%d",&n)==1);
	
	// Confidence
	for(i=0;i<n;i++)
		assert(scanf("%d",&confidence[i])==1);
	
	// Host and Protocol
	for(i=1;i<n;i++)
		assert(scanf("%d %d",&host[i],&protocol[i])==2);
	
	// Answer
	printf("%d\n",findSample(n,confidence,host,protocol));
	return 0;
}
/**/

Compilation message (stderr)

friend.cpp:185:1: warning: "/*" within comment [-Wcomment]
  185 | /**/
      |

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