Submission #883418

#	Time	Username	Problem	Language	Result	Execution time	Memory
883418		dimashhh	Cat in a tree (BOI17_catinatree)	C++17	11 / 100	13 ms	9444 KiB

catinatree

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 1501,MOD = 1e9 + 7;

int n,d,dp[N][N];
vector<int> g[N];
void dfs(int v,int pr = -1){
    dp[v][0] = 1;
    for(int to:g[v]){
        if(to == pr) continue;
        dfs(to,v);
        dp[v][0] += dp[to][d - 1];
    }
    for(int dep = 1;dep <= n;dep++){
        if(d - dep - 1 < dep - 1){
            for(int to:g[v]){
                dp[v][dep] += dp[to][dep - 1];
            }
            continue;
        }
        int mx = 0;
        for(int to:g[v]){
            if(to == pr) continue;
            dp[v][dep] += dp[to][d - dep - 1];
            mx = max(mx,dp[to][dep - 1] - dp[to][d - dep -1 ]);
        }
        dp[v][dep] += mx;
    }
    for(int i = n;i >= 0;i--){
        dp[v][i] = max(dp[v][i + 1],dp[v][i]);
        // cout << v << ' ' << dp[v][i] << '\n';
    }
}
void test(){
    cin >> n >> d;
    for(int i = 2;i <= n;i++){
        int x;
        cin >> x;
        ++x;
        g[x].push_back(i);
    }
    dfs(1);
    cout << dp[1][0];
}
main(){
    ios_base::sync_with_stdio(0);cin.tie(0);
    int T = 1;
    // cin >> T;
    while(T--)
        test();
}

Compilation message (stderr)

catinatree.cpp:46:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   46 | main(){
      | ^~~~

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