Submission #639586

#	Time	Username	Problem	Language	Result	Execution time	Memory
639586		classic	Birthday gift (IZhO18_treearray)	C++14	0 / 100	0 ms	212 KiB

treearray

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

const int LOG = 20;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n, m, q;
    cin >> n >> m >> q;
    vector<vector<int>> adj(n);
    for (int i = 0; i < n - 1; i++) {
        int u, v;
        cin >> u >> v;
        u--;
        v--;
        adj[u].emplace_back(v);
        adj[v].emplace_back(u);
    }
    vector<int> a(m);
    for (int i = 0; i < m; i++) {
        cin >> a[i];
        a[i]--;
    }
    vector<int> dep(n);
    vector<vector<int>> anc(LOG, vector<int>(n, -1));
    function<void(int, int)> dfs = [&](int u, int p) {
        anc[0][u] = p;
        for (int i = 1; i < LOG; i++) {
            if (anc[i - 1][u] != -1) {
                anc[i][u] = anc[i - 1][anc[i - 1][u]];
            }
        }
        for (int v : adj[u]) {
            if (v != p) {
                dep[v] = dep[u] + 1;
                dfs(v, u);
            }
        }
    };
    dfs(0, -1);
    function<int(int, int)> lca = [&](int u, int v) {
        if (dep[u] < dep[v]) {
            swap(u, v);
        }
        int x = dep[u] - dep[v];
        for (int i = LOG - 1; i >= 0; i--) {
            if (x & (1 << i)) {
                u = anc[i][u];
            }
        }
        if (u == v) {
            return u;
        }
        for (int i = LOG - 1; i >= 0; i--) {
            if (anc[i][u] != anc[i][v]) {
                u = anc[i][u];
                v = anc[i][v];
            }
        }
        return anc[0][u];
    };
    vector<set<int>> s(n), s1(n);
    for (int i = 0; i < m; i++) {
        if (i < m - 1) {
            s[lca(a[i], a[i + 1])].insert(i);
        }
        s1[a[i]].insert(i);
    }
    while (q--) {
        int op;
        cin >> op;
        if (op == 1) {
            int pos, v;
            cin >> pos >> v;
            pos--;
            v--;
            s1[a[pos]].erase(pos);
            s1[v].insert(pos);
            if (pos < m - 1) {
                s[lca(a[pos], a[pos + 1])].erase(pos);
                s[lca(v, a[pos + 1])].insert(pos);
            }
            if (pos > 0) {
                s[lca(a[pos - 1], a[pos])].erase(pos - 1);
                s[lca(a[pos - 1], v)].insert(pos - 1);
            }
            a[pos] = v;
        } else {
            int l, r, k;
            cin >> l >> r >> k;
            l--;
            r--;
            k--;
            set<int>::iterator it = s[k].lower_bound(l);
            if (it != s[k].end() && *it < r) {
                cout << *it << ' ' << *it + 1 << '\n';
                continue;
            }
            it = s1[k].lower_bound(l);
            if (it != s1[k].end() && *it <= r) {
                cout << *it << ' ' << *it << '\n';
                continue;
            }
            cout << -1 << ' ' << -1 << '\n';
        }
    }
    return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 18
• Subtask 3: 0 / 26
• Subtask 4: 0 / 44