oj.uz

답안 #848509

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
848509 2023-09-12T20:02:31 Z qthang2k11 Chase (CEOI17_chase) C++17
40 / 100
 373 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;
	}
	
	void debug(int x) {
		#ifndef LOCAL
		return;
		#endif
		cerr << string(15, '=') << '\n';
		for (int i = 0; i <= k; i++)
			for (int j = 0; j < 2; j++)
				fprintf(stderr, "dp[%d][%d][%d] = %lld\n", x, i, j, val[i][j]);
		cerr << string(15, '=') << '\n';
	}
};

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());
	dp[x].debug(x);
}

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() {
#ifndef LOCAL
	cin.tie(0)->sync_with_stdio(0); // ====================================================	
#endif
	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];
		fprintf(stderr, "s[%d] = %lld\n", x, s[x]);
	}
	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 21 ms 169048 KB Output is correct
2 Correct 22 ms 169104 KB Output is correct
3 Correct 22 ms 169052 KB Output is correct
4 Correct 22 ms 169036 KB Output is correct
5 Correct 22 ms 169048 KB Output is correct
6 Correct 21 ms 169040 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 21 ms 169048 KB Output is correct
2 Correct 22 ms 169104 KB Output is correct
3 Correct 22 ms 169052 KB Output is correct
4 Correct 22 ms 169036 KB Output is correct
5 Correct 22 ms 169048 KB Output is correct
6 Correct 21 ms 169040 KB Output is correct
7 Correct 27 ms 174672 KB Output is correct
8 Correct 26 ms 174808 KB Output is correct
9 Correct 24 ms 172368 KB Output is correct
10 Correct 25 ms 172376 KB Output is correct
11 Correct 24 ms 172372 KB Output is correct
12 Correct 23 ms 172376 KB Output is correct

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 373 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 21 ms 169048 KB Output is correct
2 Correct 22 ms 169104 KB Output is correct
3 Correct 22 ms 169052 KB Output is correct
4 Correct 22 ms 169036 KB Output is correct
5 Correct 22 ms 169048 KB Output is correct
6 Correct 21 ms 169040 KB Output is correct
7 Correct 27 ms 174672 KB Output is correct
8 Correct 26 ms 174808 KB Output is correct
9 Correct 24 ms 172368 KB Output is correct
10 Correct 25 ms 172376 KB Output is correct
11 Correct 24 ms 172372 KB Output is correct
12 Correct 23 ms 172376 KB Output is correct
13 Runtime error 373 ms 524288 KB Execution killed with signal 9
14 Halted 0 ms 0 KB -