제출 #939236

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
939236		vjudge1	Chase (CEOI17_chase)	C++17	20 / 100	4041 ms	24148 KiB

chase

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define pii pair<int,int>
using namespace __gnu_pbds;
using namespace std;
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define f first
#define int long long
#define s second
#define pii pair<int,int>
template<class T>bool umax(T &a,T b){if(a<b){a=b;return true;}return false;}
template<class T>bool umin(T &a,T b){if(b<a){a=b;return true;}return false;}
typedef tree<int, null_type, less_equal<int>, rb_tree_tag,
	tree_order_statistics_node_update> ordered_set;
const int N=3e5 + 5	;
const int inf = 1e17 + 7;
const int mod = 998244353;

int n,m,k,ans = -inf;
int u;
vector<int>g[N],a(N),b(N),c(N),d(N);

void dfs(int x, int pr, int cnt1){
	cnt1 += c[x];
	if(b[x] == 1){
		for(auto to:g[x]){
			c[x] += c[to];
			c[to] = 0;
		}
	}
	d[x] = cnt1;
	for(auto to:g[x]){
		if(to == pr)continue;
		dfs(to,x,cnt1);
	}
}

void dfs1(int x, int pr, int cnt2){
	cnt2 += c[x];
	
	
	umax(ans,cnt2-d[x]);
	
	for(auto to:g[x]){
		if(to != pr)dfs1(to,x,cnt2);
	}
	
}
/*
12 2
2 3 3 8 1 5 6 7 8 3 5 4
2 1
2 7
3 4
4 7
7 6
5 6
6 8
6 9
7 10
10 11
10 12
*/
void solve(){
	
	
	cin>>n>>m;
	
	for(int i = 1;i<=n;i++){
		cin>>a[i];
	}
	
	for(int i = 1;i<n;i++){
		int a,b;
		cin>>a>>b;
		g[a].pb(b);
		g[b].pb(a);
	}
	
	for(int i = 1;i<=n;i++){
		
		for(int mask = 0;mask<(1<<n);mask++){
			if(__builtin_popcount(mask) > m)continue;
			
			for(int j = 1;j<=n;j++){
				b[j] = 0;
				c[j] = a[j];
				d[j] = 0;
			}
			for(int j = 0;j<n;j++){
				if(((mask>>j)&1) == 1){
					b[j + 1] = 1;
				}
			}
			u = i;
			dfs(i,-1,0);
			dfs1(i,-1,0);
		}
		
	}
	
	
	
	
	cout<<ans<<"\n";
	
	
}

signed main()
{
//	freopen("seq.in", "r", stdin);
//  freopen("seq.out", "w", stdout);
	ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
	int tt=1;//cin>>tt>>n;
	while(tt--)solve();

}

• Subtask 1: 20 / 20
• Subtask 2: 0 / 20
• Subtask 3: 0 / 30
• Subtask 4: 0 / 30