oj.uz

답안 #848510

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
848510 2023-09-12T20:03:49 Z qthang2k11 Chase (CEOI17_chase) C++17
40 / 100
 394 ms 524288 KB 
#include <bits/stdc++.h>
using namespace std;

#ifndef LOCAL
#define fprintf(...) {}
#endif

using ll = long long;

const int N = 1e5 + 5;

template<class X, class Y>
inline void maxi(X &x, Y y) {
	if (x < y) x = y;
}

vector<int> adj[N], g[N];
int n, k, a[N];
ll s[N];

ll ans = 0, INF;

struct Node {
	ll val[101][2];
	
	Node() { 
		memset(val, -63, sizeof val); 
	}
	
	void maxi_(const Node &other) {
		for (int i = 0; i <= k; i++)
			for (int j = 0; j < 2; j++)
				maxi(val[i][j], other.val[i][j]);
	}
	
	void deal(const Node &other, const int &x, const int &y) { // update from y to x
		for (int i = 0; i <= k; i++) {
			for (int j = 0; j < 2; j++) {
				ll cur = other.val[i][j];
				// if (i < k) maxi(val[i + 1][1], cur + s[x] - a[y] + (j ? a[y] : 0));
				if (i < k) {
					if (j) maxi(val[i + 1][1], cur + s[x] - a[y]);
					else maxi(val[i + 1][1], cur + s[x] - a[y]);
					maxi(val[i + 1][1], cur + s[x] - a[y] - (j ? a[x] : 0));
				}
				// maxi(val[i][0], cur + (j ? a[y] : 0));
				maxi(val[i][0], cur/* + (j ? a[x] : 0)*/);
			}
		}
	}
	
	Node deal_(const int &x, const int &y) { // update from y to x
		Node ans;
		for (int i = 0; i <= k; i++) {
			for (int j = 0; j < 2; j++) {
				ll cur = val[i][j];
				// if (i < k) maxi(ans.val[i + 1][1], cur + s[x] - a[y] + (j ? a[y] : 0));
				if (i < k) {
					if (j) maxi(ans.val[i + 1][1], cur + s[x] - a[y]);
					else maxi(ans.val[i + 1][1], cur + s[x] - a[y]);
					maxi(ans.val[i + 1][1], cur + s[x] - a[y] - (j ? a[x] : 0));
				}
				// maxi(ans.val[i][0], cur + (j ? a[y] : 0));
				maxi(ans.val[i][0], cur/* + (j ? a[x] : 0)*/);
			}
		}
		return ans;
	}
	
	ll res() const {
		ll ans = 0;
		for (int i = 0; i <= k; i++)
			for (int j = 0; j < 2; j++)
				maxi(ans, val[i][j]);
		return ans;
	}

};

vector<Node> pref[N], suf[N];
Node dp[N];

void dfs_init(int x, int p) {
	for (int y: adj[x]) {
		if (y == p) continue;
		g[x].emplace_back(y);
		dfs_init(y, x);
	}
}

void dfs(int x) {
	pref[x].resize(g[x].size());
	suf[x].resize(g[x].size());
	for (int y: g[x]) dfs(y);
	for (int i = 0, o = g[x].size(); i < o; i++) {
		int y = g[x][i];
		auto &p = pref[x][i];
		if (i) p.maxi_(pref[x][i - 1]);
		p.deal(dp[y], x, y);
	}
	for (int o = g[x].size(), i = o - 1; i >= 0; i--) {
		int y = g[x][i];
		auto &p = suf[x][i];
		if (i < o - 1) p.maxi_(suf[x][i + 1]);
		p.deal(dp[y], x, y);
	}
	if (!g[x].empty()) dp[x] = pref[x].back();
	// else {
		maxi(dp[x].val[0][0], 0);
		if (k > 0) maxi(dp[x].val[1][1], s[x]);
	// }
	maxi(ans, dp[x].res());
}

void dfs_reroot(int x, Node down) {
	maxi(down.val[0][0], 0);
	if (k > 0) maxi(down.val[1][1], s[x]);
	maxi(ans, down.res());
	for (int i = 0, o = g[x].size(); i < o; i++) {
		int y = g[x][i];
		Node cur = down;
		if (i > 0) cur.maxi_(pref[x][i - 1]);
		if (i + 1 < o) cur.maxi_(suf[x][i + 1]);
		dfs_reroot(y, cur.deal_(y, x));
	}
}

int32_t main() {
	cin.tie(0)->sync_with_stdio(0);
	cin >> n >> k;
	for (int i = 1; i <= n; i++)
		cin >> a[i];
	for (int i = 1; i < n; i++) {
		int x, y;
		cin >> x >> y;
		adj[x].emplace_back(y);
		adj[y].emplace_back(x);
	}
	for (int x = 1; x <= n; x++) {
		for (int y: adj[x])
			s[x] += a[y];
	}
	dfs_init(1, 0);
	dfs(1);
	dfs_reroot(1, Node());
	cout << ans;
	return 0;
}

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 169040 KB Output is correct
2 Correct 22 ms 169048 KB Output is correct
3 Correct 21 ms 169048 KB Output is correct
4 Correct 22 ms 169100 KB Output is correct
5 Correct 22 ms 169180 KB Output is correct
6 Correct 21 ms 169084 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 169040 KB Output is correct
2 Correct 22 ms 169048 KB Output is correct
3 Correct 21 ms 169048 KB Output is correct
4 Correct 22 ms 169100 KB Output is correct
5 Correct 22 ms 169180 KB Output is correct
6 Correct 21 ms 169084 KB Output is correct
7 Correct 27 ms 174680 KB Output is correct
8 Correct 26 ms 174676 KB Output is correct
9 Correct 23 ms 172112 KB Output is correct
10 Correct 26 ms 172224 KB Output is correct
11 Correct 24 ms 172380 KB Output is correct
12 Correct 24 ms 172468 KB Output is correct

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 394 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #4
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 169040 KB Output is correct
2 Correct 22 ms 169048 KB Output is correct
3 Correct 21 ms 169048 KB Output is correct
4 Correct 22 ms 169100 KB Output is correct
5 Correct 22 ms 169180 KB Output is correct
6 Correct 21 ms 169084 KB Output is correct
7 Correct 27 ms 174680 KB Output is correct
8 Correct 26 ms 174676 KB Output is correct
9 Correct 23 ms 172112 KB Output is correct
10 Correct 26 ms 172224 KB Output is correct
11 Correct 24 ms 172380 KB Output is correct
12 Correct 24 ms 172468 KB Output is correct
13 Runtime error 394 ms 524288 KB Execution killed with signal 9
14 Halted 0 ms 0 KB -