Submission #135727

#	Time	Username	Problem	Language	Result	Execution time	Memory
135727		popovicirobert	Cat in a tree (BOI17_catinatree)	C++14	0 / 100	6 ms	5112 KiB

catinatree

#include <bits/stdc++.h>
#define lsb(x) (x & (-x))
#define ll long long
#define ull unsigned long long
// 217
// 44


/*const int MOD = (int) 1e9 + 7;

inline int lgput(int a, int b) {
    int ans = 1;
    while(b > 0) {
        if(b & 1) ans = (1LL * ans * a) % MOD;
        b >>= 1;
        a = (1LL * a * a) % MOD;
    }
    return ans;
}

inline void mod(int &x) {
    if(x >= MOD)
        x -= MOD;
}

inline void add(int &x, int y) {
    x += y;
    mod(x);
}

inline void sub(int &x, int y) {
    x += MOD - y;
    mod(x);
}

inline void mul(int &x, int y) {
    x = (1LL * x * y) % MOD;
}*/

/*int fact[], invfact[];

inline void prec(int n) {
    fact[0] = 1;
    for(int i = 1; i <= n; i++) {
        fact[i] = (1LL * fact[i - 1] * i) % MOD;
    }
    invfact[n] = lgput(fact[n], MOD - 2);
    for(int i = n - 1; i >= 0; i--) {
        invfact[i] = (1LL * invfact[i + 1] * (i + 1)) % MOD;
    }
}

inline int comb(int n, int k) {
    if(n < k) return 0;
    return (1LL * fact[n] * (1LL * invfact[k] * invfact[n - k] % MOD)) % MOD;
}*/

using namespace std;

const int MAXN = (int) 2e5;

vector <int> g[MAXN + 1];
int lvl[MAXN + 1];

vector < pair <int, int> > nodes;

void dfs(int nod, int par) {
    lvl[nod] = lvl[par] + 1;
    for(auto it : g[nod]) {
        if(it != par) {
            dfs(it, nod);
        }
    }
    nodes.push_back({-lvl[nod], nod});
}

bool vis[MAXN + 1];

void dfs1(int nod, int d) {
    if(d == 0 || vis[nod]) {
        return ;
    }
    vis[nod] = 1;
    for(auto it : g[nod]) {
        dfs1(it, d - 1);
    }
}

int main() {
    //ifstream cin("A.in");
    //ofstream cout("A.out");
    int i, n, d;
    ios::sync_with_stdio(false);
    cin.tie(0), cout.tie(0);

    cin >> n >> d;
    d = min(d, n);

    for(i = 2; i <= n; i++) {
        int par;
        cin >> par;
        g[par + 1].push_back(i);
        g[i].push_back(par + 1);
    }

    dfs(1, 0);
    sort(nodes.begin(), nodes.end());

    int ans = 0;
    for(auto it : nodes) {
        if(vis[it.second] == 0) {
            ans++;
            dfs1(it.second, d);
        }
    }

    cout << ans;

    return 0;
}

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