Submission #430980

#	Time	Username	Problem	Language	Result	Execution time	Memory
430980		tengiz05	Regions (IOI09_regions)	C++17	55 / 100	8096 ms	97300 KiB

regions

#include <bits/stdc++.h>
using i64 = long long;
constexpr int N = 2e5, R = 500;
int ans[R][R];
std::vector<int> e[N], c[R * R];
int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int n, m, q;
    std::cin >> n >> m >> q;
    std::vector<int> a(n);
    std::cin >> a[0];
    for (int i = 1, p; i < n; i++) {
        std::cin >> p >> a[i];
        p--;
        e[p].push_back(i);
    }
    for (int i = 0; i < n; i++) {
        c[--a[i]].push_back(i);
    }
    std::vector<int> in(n), out(n);
    int timeStamp = 0;
    std::function<void(int)> dfs = [&](int u) {
        in[u] = timeStamp++;
        for (auto v : e[u]) {
            dfs(v);
        }
        out[u] = timeStamp;
    };
    dfs(0);
    auto is = [&](int u, int v) { return in[u] < in[v] && out[u] >= out[v]; };
    if (m <= 500) {
        std::vector<int> last;
        std::function<void(int)> dfs2 = [&](int u) {
            std::vector<int> t(R);
            for (auto v : e[u]) {
                dfs2(v);
                for (int i = 0; i < R; i++) {
                    t[i] += last[i];
                }
            }
            t[a[u]]++;
            for (int i = 0; i < R; i++) {
                ans[a[u]][i] += t[i];
            }
            last = t;
        };
        dfs2(0);
        while (q--) {
            int r1, r2;
            std::cin >> r1 >> r2;
            r1--;
            r2--;
            std::cout << ans[r1][r2] << std::endl;
        }
        return 0;
    }
    while (q--) {
        int r1, r2;
        std::cin >> r1 >> r2;
        r1--;
        r2--;
        int ans = 0;
        for (auto u : c[r1]) {
            for (auto v : c[r2]) {
                if (is(u, v)) {
                    ans++;
                }
            }
        }
        std::cout << ans << std::endl;
    }
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 40 / 85