Submission #107308

#	Time	Username	Problem	Language	Result	Execution time	Memory
107308		forestryks	Ball Machine (BOI13_ballmachine)	C++14	22.50 / 100	1080 ms	47608 KiB

ballmachine

///////////////////////////////////////////////////////////////////////////////////////////////
#include <bits/stdc++.h>
using namespace std;

#define mp make_pair
#define pb push_back
#define FAST_IO ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0)
#define FILE_IO(x) freopen((string(x) + ".in").c_str(), "r", stdin); freopen((string(x) + ".out").c_str(), "w", stdout)
#define f first
#define s second
#define x1 x1qwer
#define y1 y1qwer
#define right right123
#define left left123
#define foreach(it, v) for (auto it : v)
#define rep(it, n) for (int it = 0; it < n; ++it)
#define forin(it, l, r) for (int it = l; it < r; ++it)
#define all(x) x.begin(), x.end()

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
const double DINF = numeric_limits<double>::infinity();
const ll MOD = 1e9 + 7;
const double EPS = 1e-7;
ll gcd(ll a, ll b) { return b ? gcd(b, a % b) : a; }
mt19937 mmtw_(MOD);
uniform_int_distribution<ll> rd_;
ll randomll() { return rd_(mmtw_);}
ll rnd(ll x, ll y) { return rd_(mmtw_) % (y - x + 1) + x; }
////////////////////////////////////////////////////////////////////////////////////////////////

const int MAXN = 1e6 + 5;
int n, q;
vector<int> g[MAXN];
int root;
int up[MAXN][20];
set<pair<int, int>> s;
int mn[MAXN];
int tin[MAXN];
bool used[MAXN];
int h[MAXN];

void dfsm(int v) {
    mn[v] = v;
    for (auto to : g[v]) {
        h[to] = h[v] + 1;
        dfsm(to);
        mn[v] = min(mn[v], mn[to]);
    }

    sort(all(g[v]), [&](int a, int b){
        return mn[a] < mn[b];
    });
}

int tt = 0;
void dfs(int v) {
    for (int i = 1; i < 20; ++i) {
        up[v][i] = up[up[v][i - 1]][i - 1];
    }
    for (auto to : g[v]) {
        dfs(to);
    }
    tin[v] = tt++;
}

int main() {
    FAST_IO;
    cin >> n >> q;
    rep(i, n) {
        int p;
        cin >> p;
        p--;
        if (p == -1) {
            root = i;
        } else {
            g[p].push_back(i);
            up[i][0] = p;
        }
    }

    dfsm(root);
    dfs(root);

    rep(i, n) {
        s.insert({tin[i], i});
    }

    // for (auto &it : s) {
    //     cout << it.f << ' ' << it.s << endl;
    // }

    for (int i = 0; i < q; ++i) {
        int t;
        cin >> t;
        if (t == 1) {
            int k, r = -1;
            cin >> k;
            rep(j, k) {
                used[s.begin()->s] = true;
                r = s.begin()->s;
                s.erase(s.begin());
            }

            cout << r + 1 << '\n';
        } else {
            int v, r = 0;
            cin >> v;
            v--;
            int w = v;
            for (int i = 19; i >= 0; --i) {
                if (used[up[v][i]]) {
                    v = up[v][i];
                }
            }
            used[v] = false;
            s.insert({tin[v], v});
            cout << h[w] - h[v] << '\n';
        }
    }
}

Compilation message (stderr)

ballmachine.cpp: In function 'int main()':
ballmachine.cpp:110:20: warning: unused variable 'r' [-Wunused-variable]
             int v, r = 0;
                    ^

• Subtask 1: 3.8461538461538463 / 25
• Subtask 2: 10.714285714285714 / 30
• Subtask 3: 5.714285714285714 / 40
• Subtask 4: 2.2222222222222223 / 5