제출 #1155644

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1155644		dpsaveslives	Cat in a tree (BOI17_catinatree)	C++20	100 / 100	35 ms	20804 KiB

catinatree

#include <bits/stdc++.h>
using namespace std;
int N,D;
const int MAXN = 2e5+5;
int dp[MAXN],cl[MAXN]; //maximum value, closest picked node
vector<int> adj[MAXN];
void dfs(int u, int p){
    cl[u] = 0; dp[u] = 1;
    for(auto v : adj[u]){
        if(v != p){
            dfs(v,u);
            dp[u] += dp[v];
            if(cl[u]+cl[v]+1 < D){
                --dp[u];
                cl[u] = max(cl[u],cl[v]+1);
            }
            else{
                cl[u] = min(cl[u],cl[v]+1);
            }
        }
    }
}
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    cin >> N >> D;
    for(int i = 2;i<=N;++i){
        int u; cin >> u; ++u;
        adj[u].push_back(i); adj[i].push_back(u);
    }
    dfs(1,0);
    cout << dp[1] << "\n";
    return 0;
}

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