Submission #441629

#	Time	Username	Problem	Language	Result	Execution time	Memory
441629		vishesh312	Birthday gift (IZhO18_treearray)	C++17	100 / 100	1174 ms	77656 KiB

treearray

#include "bits/stdc++.h"
using namespace std;
/*
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
using ordered_set = tree<int, null_type, less<int>, rb_tree_tag, tree_order_statistics_node_update>;
*/

#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
#define sz(x) (int)(x).size()

using ll = long long;
const int mod = 1e9+7;

vector<vector<int>> adj;
vector<int> depth;
vector<array<int, 20>> up;

void dfs(int u, int p = -1) {
    for (int v : adj[u]) {
        if (v != p) {
            depth[v] = depth[u] + 1;
            up[v][0] = u;
            for (int l = 1; l < 20; ++l) {
                up[v][l] = up[up[v][l-1]][l-1];
            }
            dfs(v, u);
        }
    }
}

void solve(int tc) {
    int n, m, q;
    cin >> n >> m >> q;
    adj.resize(n); up.resize(n); depth.resize(n);
    for (int i = 0; i < n-1; ++i) {
        int u, v;
        cin >> u >> v;
        --u, --v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
    dfs(0);
    auto get_lca = [&] (int u, int v) {
        if (depth[u] < depth[v])
            swap(u, v);
        int k = depth[u] - depth[v];
        for (int l = 19; l >= 0; --l)
            if (k & (1<<l))
                u = up[u][l];
        if (u == v)
            return u;
        for (int l = 19; l >= 0; --l) {
            if (up[u][l] != up[v][l]) {
                u = up[u][l];
                v = up[v][l];
            }
        }
        return up[u][0];
    };
    vector<set<int>> lca(n);
    vector<set<int>> pos(n);
    vector<int> a(m);
    for (auto &x : a) {
        cin >> x;
        --x;
    }
    for (int i = 0; i < m; ++i)
        pos[a[i]].insert(i);
    for (int i = 0; i < m-1; ++i) {
        int u = get_lca(a[i], a[i+1]);
        lca[u].insert(i);
    }
    while (q--) {
        int x;
        cin >> x;
        if (x == 1) {
            int p, v;
            cin >> p >> v;
            --p, --v;
            pos[a[p]].erase(p);
            pos[v].insert(p);
            if (p) {
                lca[get_lca(a[p-1], a[p])].erase(p-1);
                lca[get_lca(a[p-1], v)].insert(p-1);
            }
            if (p < m-1) {
                lca[get_lca(a[p], a[p+1])].erase(p);
                lca[get_lca(v, a[p+1])].insert(p);
            }
            a[p] = v;
        } else {
            int l, r, v;
            cin >> l >> r >> v;
            --l, --r, --v;
            auto it = pos[v].lower_bound(l);
            int p = *it;
            if (it != pos[v].end() and p <= r) {
                cout << p+1 << " " << p+1 << '\n';
                continue;
            }
            it = lca[v].lower_bound(l);
            p = *it;
            if (it != lca[v].end() and p < r) {
                cout << p+1 << " " << p+2 << '\n';
                continue;
            }
            cout << "-1 -1\n";
        }
    }
}

signed main() {
    cin.tie(0)->sync_with_stdio(0);
    int tc = 1;
    //cin >> tc;
    for (int i = 1; i <= tc; ++i) solve(i);
    return 0;
}

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