Submission #889441

#	Time	Username	Problem	Language	Result	Execution time	Memory
889441		makrav	Birthday gift (IZhO18_treearray)	C++14	100 / 100	761 ms	98424 KiB

treearray

#define _USE_MATH_DEFINES
#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef vector<int> vei;
typedef vector<vei> vevei;

#define all(a) (a).begin(), (a).end()
#define sz(a) (int) a.size()
#define con cout << "NO\n"
#define coe cout << "YES\n";
#define str string
#define pb push_back
#define ff first
#define sc second
#define ss second
#define pii pair<int, int>
#define mxe max_element
#define mne min_element
#define stf shrink_to_fit
#define f(i, l, r) for (int i = (l); i < (r); i++)
#define double ld

struct LCA {
    int n;
    vector<vector<int>> g, up;
    vector<int> tin, tout;
    int timer = 0, l;

    LCA() = default;
    LCA(int n_, vector<vector<int>>& g_) {
        n = n_;
        g = g_;
        l = (int)log2(n) + 1;
        up.assign(n, vector<int>(l, 0));
        tin.assign(n, 0);
        tout.assign(n, 0);
        dfs(0, 0);
    }

    void dfs(int v, int p) {
        tin[v] = timer++;
        up[v][0] = p;
        f(i, 1, l) {
            up[v][i] = up[up[v][i - 1]][i - 1];
        }

        for (auto& u : g[v]) {
            if (u != p) {
                dfs(u, v);
            }
        }
        tout[v] = timer++;
    }

    bool parent(int a, int b) {
        return tin[a] <= tin[b] && tout[a] >= tout[b];
    }

    int lca(int a, int b) {
        if (parent(a, b)) return a;
        if (parent(b, a)) return b;

        for (int i = l - 1; i >= 0; i--) {
            if (!parent(up[a][i], b)) {
                a = up[a][i];
            }
        }
        return up[a][0];
    }
};

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);

    int n, m, q; cin >> n >> m >> q;
    vector<vector<int>> g(n);
    f(i, 0, n - 1) {
        int u, v; cin >> u >> v;
        u--; v--;
        g[u].pb(v);
        g[v].pb(u);

    }
    LCA lc(n, g);

    vector<int> a(m);
    f(i, 0, m) { cin >> a[i]; a[i]--; }
    vector<int> lcas(m - 1);
    vector<set<int>> pos(n), pos2(n);
    f(i, 0, m - 1) {
        lcas[i] = lc.lca(a[i], a[i + 1]);
        pos[lcas[i]].insert(i);
        pos2[a[i]].insert(i);
    }
    pos2[a[m - 1]].insert(m - 1);
    while (q--) {
        int t; cin >> t;
        if (t == 1) {
            int p, v; cin >> p >> v;
            p--;
            v--;
            pos2[a[p]].erase(p);
            pos2[v].insert(p);

            if (p > 0) {
                pos[lcas[p - 1]].erase(p - 1);
                lcas[p - 1] = lc.lca(a[p - 1], v);
                pos[lcas[p - 1]].insert(p - 1);
            }
            if (p < m - 1) {
                pos[lcas[p]].erase(p);
                lcas[p] = lc.lca(v, a[p + 1]);
                pos[lcas[p]].insert(p);
            }

            a[p] = v;
        }
        else {
            int l, r, x; cin >> l >> r >> x;
            l--; r--; x--;
            auto it = pos2[x].lower_bound(l);
            if (it != pos2[x].end() && *it <= r) {
                cout << *it + 1 << ' ' << *it + 1 << '\n';
                continue;
            }
            auto it2 = pos[x].lower_bound(l);
            if (r - l + 1 >= 2 && it2 != pos[x].end() && *it2 <= r - 1) {
                cout << *it2 + 1 << ' ' << *it2 + 2 << '\n';
                continue;
            }
            cout << "-1 -1\n";
        }
    }


    return 0;
}

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