제출 #985597

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
985597		OAleksa	Cat in a tree (BOI17_catinatree)	C++14	51 / 100	41 ms	26060 KiB

catinatree

#include <bits/stdc++.h>
#define f first
#define s second
using namespace std;
const int N = 1569;
int n, d, dp[N][N], dp2[N][N];
vector<int> g[N];
void dfs(int v, int p) {
	vector<int> ch;
	for (auto u : g[v]) {
		if (u == p)
			continue;
		dfs(u, v);
		ch.push_back(u);
	}
	if (ch.empty()) 
		dp[v][0] = dp2[v][0] = 1;
	else {
		vector<int> sum(N);
		for (auto u : ch) {
			for (int j = 0;j <= d;j++)
				sum[j] += dp2[u][j];
		}
		for (int j = 1;j <= d;j++) {
			for (auto u : ch) {
				int x = d - j;
				if (x < j) {
					int sm = sum[j - 1] - dp2[u][j - 1];
					dp[v][j] = max(dp[v][j], sm + dp[u][j - 1]);
				}
				else {
					int sm = sum[x - 1] - dp2[u][x - 1];
					dp[v][j] = max(dp[v][j], sm + dp[u][j - 1]);
				}
			}
		}
		dp[v][0] = 1;
		for (auto u : ch) 
			dp[v][0] += dp[u][d - 1];
		for (int j = d;j >= 0;j--)
			dp2[v][j] = max(dp2[v][j + 1], dp[v][j]);
	}
}
signed main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  int tt = 1;
  //cin >> tt;
  while (tt--) {
  	cin >> n >> d;
  	for (int i = 2;i <= n;i++) {
  		int x;
  		cin >> x;
  		++x;
  		g[x].push_back(i);
  		g[i].push_back(x);
  	}
  	dfs(1, 0);
  	int ans = 0;
  	for (int i = 0;i <= d;i++)
  		ans = max(ans, dp[1][i]);
  	cout << ans;
  }
  return 0; 
}

• Subtask 1: 11 / 11
• Subtask 2: 40 / 40
• Subtask 3: 0 / 49