oj.uz

답안 #848538

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
848538 2023-09-12T20:59:57 Z qthang2k11 Chase (CEOI17_chase) C++17
40 / 100
 365 ms 524288 KB 
#include <bits/stdc++.h>
using namespace std;
 
#ifdef LOCAL
#undef LOCAL
#endif
 
#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> 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 i = g[x].size() - 1; i >= 0; i--) {
		int y = g[x][i];
		if (y != p) continue;
		swap(g[x][i], g[x].back());
		g[x].pop_back();
	}
	for (int y: g[x]) 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 = (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 = (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
//	freopen("chase.03.01.in", "r", stdin);
	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;
		g[x].emplace_back(y);
		g[y].emplace_back(x);
	}
	for (int x = 1; x <= n; x++) {
		for (int y: g[x])
			s[x] += a[y];
		fprintf(stderr, "s[%d] = %lld\n", x, s[x]);
	}
//	cerr << "?\n";
	dfs_init(1, 0);
//	cerr << "?\n";
	// return 0;
	dfs(1);
//	cerr << "?\n";
	dfs_reroot(1, Node()); // ============================================================
//	cerr << "?\n";
	cout << ans;
	return 0;
}

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 166796 KB Output is correct
2 Correct 21 ms 166684 KB Output is correct
3 Correct 20 ms 166736 KB Output is correct
4 Correct 21 ms 166748 KB Output is correct
5 Correct 20 ms 166748 KB Output is correct
6 Correct 21 ms 166748 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 22 ms 166796 KB Output is correct
2 Correct 21 ms 166684 KB Output is correct
3 Correct 20 ms 166736 KB Output is correct
4 Correct 21 ms 166748 KB Output is correct
5 Correct 20 ms 166748 KB Output is correct
6 Correct 21 ms 166748 KB Output is correct
7 Correct 27 ms 172224 KB Output is correct
8 Correct 25 ms 172376 KB Output is correct
9 Correct 23 ms 169820 KB Output is correct
10 Correct 24 ms 169816 KB Output is correct
11 Correct 23 ms 169808 KB Output is correct
12 Correct 23 ms 169864 KB Output is correct

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 365 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 166796 KB Output is correct
2 Correct 21 ms 166684 KB Output is correct
3 Correct 20 ms 166736 KB Output is correct
4 Correct 21 ms 166748 KB Output is correct
5 Correct 20 ms 166748 KB Output is correct
6 Correct 21 ms 166748 KB Output is correct
7 Correct 27 ms 172224 KB Output is correct
8 Correct 25 ms 172376 KB Output is correct
9 Correct 23 ms 169820 KB Output is correct
10 Correct 24 ms 169816 KB Output is correct
11 Correct 23 ms 169808 KB Output is correct
12 Correct 23 ms 169864 KB Output is correct
13 Runtime error 365 ms 524288 KB Execution killed with signal 9
14 Halted 0 ms 0 KB -