Submission #1092271

#	Time	Username	Problem	Language	Result	Execution time	Memory
1092271		TrinhKhanhDung	Cat in a tree (BOI17_catinatree)	C++14	100 / 100	34 ms	13648 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];
pair<int, int> f[MAX];

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

    auto dfs = [&](auto self, int u) -> void{
        f[u] = {1, 0};
        for(int v: adj[u]){
            self(self, v);
            f[u].fi += f[v].fi;
            if(f[u].se + f[v].se + 1 < D){
                f[u].fi--;
                maximize(f[u].se, f[v].se + 1);
            }
            else{
                minimize(f[u].se, f[v].se + 1);
            }
        }
    };

    dfs(dfs, 0);

    cout << f[0].fi << '\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: 49 / 49