Submission #879256

#	Time	Username	Problem	Language	Result	Execution time	Memory
879256		The_Samurai	Birthday gift (IZhO18_treearray)	C++17	56 / 100	4022 ms	38180 KiB

treearray

// I stand with PALESTINE




//#pragma GCC optimize("Ofast,O3")
//#pragma GCC target("avx,avx2")
#include "bits/stdc++.h"

using namespace std;
using ll = long long;
const int lg = 18;

vector<vector<int>> g, jump;
vector<int> tin, tout;
int z;

void dfs(int u) {
    if (u != 1) {
        for (int i = 1; i < lg; i++) {
            jump[i][u] = jump[i - 1][jump[i - 1][u]];
            if (!jump[i][u]) break;
        }
    }
    tin[u] = z++;
    for (int v: g[u]) {
        if (jump[0][u] == v) continue;
        jump[0][v] = u;
        dfs(v);
    }
    tout[u] = z++;
}

bool isPar(int u, int v) {
    return tin[u] <= tin[v] and tout[v] <= tout[u];
}

int lca(int u, int v) {
    if (v == 0 or isPar(u, v)) return u;
    if (u == 0 or isPar(v, u)) return v;
    for (int i = lg - 1; i >= 0; i--) {
        if (!jump[i][u] or isPar(jump[i][u], v)) continue;
        u = jump[i][u];
    }
    return jump[0][u];
}

void solve() {
    int n, m, q;
    cin >> n >> m >> q;
    g.assign(n + 1, {});
    jump.assign(lg, vector<int>(n + 1));
    tin.assign(n + 1, 0); tout.assign(n + 1, 0);
    for (int i = 1; i < n; i++) {
        int u, v;
        cin >> u >> v;
        g[u].emplace_back(v);
        g[v].emplace_back(u);
    }
    vector<int> a(m + 1);
    for (int i = 1; i <= m; i++) cin >> a[i];
    dfs(1);
    while (q--) {
        int op;
        cin >> op;
        if (op == 1) {
            int i;
            cin >> i >> a[i];
        } else {
            int l, r, root;
            cin >> l >> r >> root;
            int anc = 0;
            bool found = false;
            for (int lx = l, rx = l; rx <= r; rx++) {
                anc = lca(anc, a[rx]);
                if (anc == root) {
                    cout << lx << ' ' << rx << '\n';
                    found = true;
                    break;
                }
                if (!isPar(root, anc)) {
                    lx = rx + 1;
                    anc = 0;
                }
            }
            if (!found) cout << "-1 -1\n";
        }
    }
}

int main() {
    cin.tie(0)->sync_with_stdio(false);
#ifdef sunnatov
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    int q = 1;
//    cin >> q;
    while (q--) {
        solve();
        cout << '\n';
    }
}

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