Submission #1092028

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092028		TrinhKhanhDung	Cat in a tree (BOI17_catinatree)	C++14	51 / 100	25 ms	18648 KiB

catinatree

#include <bits/stdc++.h>
#define ll long long
#define fi first
#define se second
#define sz(x) (int)x.size()
#define ALL(v) v.begin(),v.end()
#define MASK(k) (1LL << (k))
#define BIT(x, i) (((x) >> (i)) & 1)
#define oo (ll)1e18
#define INF (ll)1e9
#define MOD (ll)(998244353)

using namespace std;

template<class T1, class T2>
    bool maximize(T1 &a, T2 b){if(a < b){a = b; return true;} return false;}

template<class T1, class T2>
    bool minimize(T1 &a, T2 b){if(a > b){a = b; return true;} return false;}

template<class T1, class T2>
    void add(T1 &a, T2 b){a += b; if(a >= MOD) a -= MOD;}

template<class T1, class T2>
    void sub(T1 &a, T2 b){a -= b; if(a < 0) a += MOD;}

template<class T>
    void cps(T &v){sort(ALL(v)); v.resize(unique(ALL(v)) - v.begin());}

const int MAX = 2e5 + 10;

int N, D;
vector<int> adj[MAX];
int f[2000][2000], old_dp[MAX], new_dp[MAX];

void dfs(int u){
    for(int v: adj[u]){
        dfs(v);
    }

//    cout << u << '\n';
    new_dp[0] = 1;
    for(int v: adj[u]){
        for(int i = D - 1; i >= 0; i--){
            old_dp[i] = max(old_dp[i + 1], new_dp[i]);
            new_dp[i] = 0;
        }
        for(int i = 0; i < D; i++){
            new_dp[i] = old_dp[i] + f[v][max(i - 1, D - i - 1)];
            if(i > 0) maximize(new_dp[i], old_dp[max(i, D - i)] + f[v][i - 1]);
        }
    }

    for(int i = D - 1; i >= 0; i--){
        f[u][i] = max(f[u][i + 1], new_dp[i]);
        new_dp[i] = 0;
    }
//    cout << u << '\n';
//    for(int i = 0; i < D; i++){
//        cout << i << ' ' << f[u][i] << '\n';
//    }
}

void solve(){
    cin >> N >> D;
    for(int i = 1; i < N; i++){
        int x; cin >> x;
        adj[x].push_back(i);
    }

    dfs(0);
    int ans = 0;
    for(int i = 0; i < D; i++) maximize(ans, f[0][i]);

    cout << ans << '\n';
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
//     freopen("cnt-mst.inp","r",stdin);
//     freopen("cnt-mst.out","w",stdout);

    int t = 1;
//    cin >> t;
    while(t--)
        solve();

    return 0;
}

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