Submission #94614

#	Time	Username	Problem	Language	Result	Execution time	Memory
94614		jasony123123	Chase (CEOI17_chase)	C++11	0 / 100	257 ms	132296 KiB

chase

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
//#include <ext/pb_ds/tree_policy.hpp>
//#include <ext/pb_ds/assoc_container.hpp>
using namespace std;
//using namespace __gnu_pbds;

#define FOR(i,start,end) for(int i=start;i<(int)(end);i++)
#define FORE(i,start,end) for(int i=start;i<=(int)end;i++)
#define RFOR(i,start,end) for(int i = start; i>end; i--)
#define RFORE(i,start,end) for(int i = start; i>=end; i--)
#define all(a) a.begin(), a.end()
#define mt make_tuple
#define mp make_pair
#define v vector
#define sf scanf
#define pf printf
#define dvar(x) cout << #x << " := " << x << "\n"
#define darr(x,n) FOR(i,0,n) cout << #x << "[" << i << "]" << " := " << x[i] << "\n"

typedef long long ll;
typedef long double ld;
typedef pair<int, int > pii;
typedef pair<ll, ll> pll;
//template <class T> using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<class T> void minn(T &a, T b) { a = min(a, b); }
template<class T> void maxx(T &a, T b) { a = max(a, b); }

void io() {
#ifdef LOCAL_PROJECT 
	freopen("input.in", "r", stdin); freopen("output.out", "w", stdout);
#else 
	/* online submission */

#endif 
	ios_base::sync_with_stdio(false); cin.tie(NULL);
}

const ll MOD = 1000000007LL;
const ll PRIME = 105943LL;
const ll INF = 1e18;
/********************CEOI 2017 Day 2 #3******************************/
const int MAXN = 100099, MAXV = 101;

int N, V;
ll P[MAXN], NEIG[MAXN];
v<int> adj[MAXN];
ll up[MAXN][MAXV], down[MAXN][MAXV], ans = 0;

void dfs(int x, int p) {
	for (auto c : adj[x]) if (c != p) {
		dfs(c, x);
		FORE(k, 1, V) {
			maxx(down[x][k], max(down[c][k], down[c][k - 1] + NEIG[c] - P[x]));
			maxx(up[x][k], max(up[c][k], up[c][k - 1] + NEIG[x] - P[c]));
		}
	}
	maxx(up[x][1], NEIG[x]);
	maxx(ans, max(down[x][V], up[x][V]));
}

void go(int x, int p) {
	v<int> chi;
	for (auto c : adj[x]) if (c != p) chi.push_back(c);
	for (auto c1 : chi) for (auto c2 : chi) if (c1 != c2) {
		FORE(k1, 0, V) {
			maxx(ans, up[c1][k1] + down[c2][V - k1]);
			if (k1 <= V - 1)
				maxx(ans, up[c1][k1] + down[c2][V - k1 - 1] + NEIG[x] - P[c1]);
		}
	}
}

int main() {
	io();
	cin >> N >> V;
	FORE(i, 1, N) cin >> P[i];
	FOR(i, 0, N - 1) {
		int a, b; cin >> a >> b;
		adj[a].push_back(b), adj[b].push_back(a);
	}
	FORE(i, 1, N)
		for (auto n : adj[i]) NEIG[i] += P[n];
//	darr(P, N + 1);
//	darr(NEIG, N + 1);
	dfs(1, -1);
	go(1, -1);
	cout << ans << "\n";
}

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