Submission #695369

#	Time	Username	Problem	Language	Result	Execution time	Memory
695369		Duy_e	Ball Machine (BOI13_ballmachine)	C++14	68.42 / 100	202 ms	23520 KiB

ballmachine

#include <bits/stdc++.h>
#define ll long long
#define rep(i, n, m) for (ll i = n; i <= m; i ++)
#define rrep(i, n, m) for (ll i = n; i >= m; i --)
using namespace std;
const long long N = 2e5 + 5;
int n, q, a[N], full[N], mi[N], up[20][N];
vector <int> d[N], order;

void dfs(int u) {
    mi[u] = u;
    for (int v: d[u])
        dfs(v), mi[u] = min(mi[u], mi[v]);
}

void dfs2(int u) {
    for (int v: d[u]) dfs2(v);
    order.push_back(u);
}

stack <int> st;
void del(int u) {
    int cnt = 0;
    rrep(i, 19, 0) if (full[up[i][u]])
        u = up[i][u], cnt += 1 << i;
    full[u] = false;
    st.push(u);
    cout << cnt << '\n';
}

int cur = 0;
void add(int k) {
    int lst = 0;
    while (st.size() && k) {
        lst = st.top();
        st.pop();
        k --;
        full[lst] = true;
    }

    while (k --) lst = order[cur ++], full[lst] = true;
    cout << lst << '\n';
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    //freopen("A.ans", "w", stdout);
    cin >> n >> q;
    rep(i, 1, n) {
        int p; cin >> p;
        d[p].push_back(i);
        up[0][i] = p;
    }

    dfs(0);
    rep(i, 1, 19) rep(j, 1, n)
        up[i][j] = up[i - 1][up[i - 1][j]];

    auto cmp = [&] (int u, int v) { return mi[u] < mi[v]; };
    rep(i, 1, n) sort(d[i].begin(), d[i].end(), cmp);

    dfs2(0);

    int t, x;

    while (q --) {
        cin >> t >> x;
        if (t == 1) add(x);
        if (t == 2) del(x);
    }

    return 0;
}

• Subtask 1: 9.615384615384615 / 25
• Subtask 2: 17.142857142857142 / 30
• Subtask 3: 40 / 40
• Subtask 4: 1.6666666666666667 / 5