제출 #731703

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
731703		Desh03	Regions (IOI09_regions)	C++17	30 / 100	8103 ms	131072 KiB

regions

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

vector<vector<int>> r, g;
vector<int> euler, in, out, fr, c;
vector<vector<pair<int, int>>> q;
int t;
const int block = 447;

void dfs(int u) {
    in[u] = t++;
    euler.push_back(u);
    for (int v : g[u])
        dfs(v);
    out[u] = t - 1;
}

void add(int x) {
    fr[c[euler[x]]]++;
}

void remove(int x) {
    fr[c[euler[x]]]--;
}

int main() {
    int n, rr, qq;
    cin >> n >> rr >> qq;
    g.resize(n), r.resize(rr), in.resize(n), out.resize(n), fr.resize(rr), c.resize(n), q.resize(qq);
    int x, h;
    cin >> h;
    h--;
    r[h].push_back(0);
    c[0] = h;
    int mx = 0;
    for (int i = 1; i < n; i++) {
        cin >> x >> h;
        x--, h--;
        r[h].push_back(i);
        g[x].push_back(i);
        c[i] = h;
        mx = max(mx, (int) r[h].size());
    }
    dfs(0);
    if (rr <= 1000 || mx > 500) {
        vector<vector<int>> ans(rr, vector<int> (rr));
        for (int i = 0; i < rr; i++) {
            sort(r[i].begin(), r[i].end(), [](const int &a, const int &b) {
                 int a1 = in[a] / block, b1 = in[b] / block;
                 return a1 == b1 ? out[a] < out[b] : a1 < b1;
            });
        }
        for (int i = 0; i < rr; i++) {
            int lb, rb;
            if (r[i].size()) lb = in[r[i][0]] + 1, rb = lb - 1;
            for (int u : r[i]) {
                int l_ = in[u] + 1, r_ = out[u];
                while (lb > l_) add(--lb);
                while (rb < r_) add(++rb);
                while (lb < l_) remove(lb++);
                while (rb > r_) remove(rb--);
                for (int j = 0; j < rr; j++) ans[i][j] += fr[j];
            }
            if (r[i].size()) for (int j = 0; j < rr; j++) fr[j] = 0;
        }
        while (qq--) {
            int a, b;
            cin >> a >> b;
            cout << ans[--a][--b] << endl;
        }
    } else {
        map<int, map<int, int>> mp;
        map<pair<int, int>, int> mp2;
        for (int i = 0; i < rr; i++) {
            sort(r[i].begin(), r[i].end(), [](const int &a, const int &b) {
                 int a1 = in[a] / block, b1 = in[b] / block;
                 return a1 == b1 ? out[a] < out[b] : a1 < b1;
            });
        }
        while (qq--) {
            int a, b, ans = 0, cnt = 0;
            cin >> a >> b;
            a--, b--;
            if (mp2.find({a, b}) != mp2.end()) {
                cout << mp2[{a, b}] << '\n';
                continue;
            }
            int lb, rb;
            if (r[a].size()) lb = in[r[a][0]] + 1, rb = lb - 1;
            for (int u : r[a]) {
                if (mp[u].find(b) != mp[u].end()) cnt += mp[u][b];
                else {
                    int l_ = in[u] + 1, r_ = out[u];
                    while (lb > l_) add(--lb);
                    while (rb < r_) add(++rb);
                    while (lb < l_) remove(lb++);
                    while (rb > r_) remove(rb--);
                    mp[u][b] = cnt;
                    ans += cnt;
                }
            }
            cout << ans << endl;
            mp2[{a, b}] = ans;
        }
    }
}

• Subtask 1: 15 / 15
• Subtask 2: 15 / 85