Submission #1261071

#	Time	Username	Problem	Language	Result	Execution time	Memory
1261071		duyanhchupapi	Cat in a tree (BOI17_catinatree)	C++20	100 / 100	47 ms	20040 KiB

catinatree

#include <bits/stdc++.h>
using namespace std; const int N = 200005;
int n, d, ans, f[N];
vector<int> g[N];
void dfs(int u,int p) {
	f[u] = 0;
	for(int v : g[u]){
		if(v == p) continue;
		dfs(v, u);
		if(f[u] + f[v] + 1 >= d) ++ans, f[u] = min(f[u], f[v] + 1);
		else f[u] = max(f[u], f[v] + 1);
	}
}
int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	cin >> n >> d; ans = 1;
	for(int i=1;i<n;++i) {
		int x;cin >> x;
		g[x].push_back(i);
		g[i].push_back(x);
	}
	dfs(0, -1);
	cout << ans;
	return 0;
}

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