oj.uz

답안 #293157

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
293157 2020-09-07T17:05:05 Z shivensinha4 Chase (CEOI17_chase) C++17
40 / 100
 4000 ms 89592 KB 
#include <bits/stdc++.h> 
using namespace std; 
#define for_(i, s, e) for (int i = s; i < (int) e; i++)
#define for__(i, s, e) for (ll i = s; i < e; i++)
typedef long long ll;
typedef vector<int> vi;
typedef pair<int, int> ii;
#define endl '\n'

const int MXN = 1e5, MXV = 100;
int n, v;
ll dp[MXN+1][MXV+1];
ll nums[MXN+1];
vi adj[MXN+1];
ll ans = 0;

void init(int p, int parent) {
	for (int i: adj[p]) if (i != parent) init(i, p);
	for_(ct, 0, v+1) {
		ll s = 0, take = 0, noTake = 0;
		for (int i: adj[p]) if (i != parent) {
			s += nums[i];
			if (ct) take = max(take, dp[i][ct-1]);
			noTake = max(noTake, dp[i][ct]);
		}
		dp[p][ct] = noTake;
		if (ct) dp[p][ct] = max(dp[p][ct], s+take);
	}
}

vector<ll> prefMax(vector<ll> k) {
	for_(i, 1, k.size()) k[i] = max(k[i], k[i-1]);
	return k;
}

vector<ll> sufMax(vector<ll> k) {
	for (int i = k.size()-2; i >= 0; i--) k[i] = max(k[i], k[i+1]);
	return k;
}

void reroot(int p, int parent, ll p0, ll p1) {
	//cout << "! " << p << " " << parent << " " << p0 << " " << p1 << endl;
	int ct = adj[p].size();
	vector<ll> take(ct), noTake(ct), takePref, takeSuf, noTakePref, noTakeSuf;
	ll s = 0;
	for_(i, 0, ct) {
		if (adj[p][i] == parent) {
			take[i] = p1; noTake[i] = p0;
		} else {
			take[i] = dp[adj[p][i]][v-1]; noTake[i] = dp[adj[p][i]][v];
		}
		s += nums[adj[p][i]];
	}
	
	takePref = prefMax(take); noTakePref = prefMax(noTake);
	takeSuf = sufMax(take); noTakeSuf = sufMax(noTake);
	//cout << p << " " << takeSuf[0] + s << " " << noTakeSuf[0] << endl;
	ans = max({ans, takeSuf[0] + s, noTakeSuf[0]});
	
	for_(i, 0, ct) {
		if (adj[p][i] == parent) continue;
		//reroot(adj[p][i], p, max(i > 0 ? noTakePref[i-1] : 0, i < ct-1 ? noTakeSuf[i+1] : 0), max(i > 0 ? takePref[i-1] : 0, i < ct-1 ? takeSuf[i+1] : 0) + s - nums[adj[p][i]]);
	}
}

int main() {
	#ifdef shiven
	freopen("test.in", "r", stdin);
	#endif
	
	ios_base::sync_with_stdio(false);
	cin.tie(0);
	
	cin >> n >> v;
	for_(i, 0, n) cin >> nums[i];
	for_(i, 0, n-1) {
		int a, b; cin >> a >> b;
		a -= 1; b -= 1;
		adj[a].push_back(b); adj[b].push_back(a);
	}
	
	if (v == 0) {
		cout << 0 << endl;
		return 0;
	}
	
	for_(i, 0, n) {
		init(i, i);
		reroot(i, i, 0, 0);
	}
	
	cout << ans << endl;

	return 0;
}

Subtask #1
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2816 KB Output is correct
2 Correct 2 ms 2688 KB Output is correct
3 Correct 2 ms 2688 KB Output is correct
4 Correct 2 ms 2688 KB Output is correct
5 Correct 2 ms 2688 KB Output is correct
6 Correct 2 ms 2688 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2816 KB Output is correct
2 Correct 2 ms 2688 KB Output is correct
3 Correct 2 ms 2688 KB Output is correct
4 Correct 2 ms 2688 KB Output is correct
5 Correct 2 ms 2688 KB Output is correct
6 Correct 2 ms 2688 KB Output is correct
7 Correct 634 ms 3704 KB Output is correct
8 Correct 54 ms 3584 KB Output is correct
9 Correct 45 ms 3704 KB Output is correct
10 Correct 632 ms 3584 KB Output is correct
11 Correct 216 ms 3584 KB Output is correct
12 Correct 88 ms 3576 KB Output is correct

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Execution timed out 4082 ms 89592 KB Time limit exceeded
2 Halted 0 ms 0 KB -

Subtask #4
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 2 ms 2816 KB Output is correct
2 Correct 2 ms 2688 KB Output is correct
3 Correct 2 ms 2688 KB Output is correct
4 Correct 2 ms 2688 KB Output is correct
5 Correct 2 ms 2688 KB Output is correct
6 Correct 2 ms 2688 KB Output is correct
7 Correct 634 ms 3704 KB Output is correct
8 Correct 54 ms 3584 KB Output is correct
9 Correct 45 ms 3704 KB Output is correct
10 Correct 632 ms 3584 KB Output is correct
11 Correct 216 ms 3584 KB Output is correct
12 Correct 88 ms 3576 KB Output is correct
13 Execution timed out 4082 ms 89592 KB Time limit exceeded
14 Halted 0 ms 0 KB -