Submission #867740

#	Time	Username	Problem	Language	Result	Execution time	Memory
867740		overwatch9	Regions (IOI09_regions)	C++17	13 / 100	876 ms	131072 KiB

regions

#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
vector <vector <int>> adj;
vector <int> col;
vector <map <int, int>> freq;
vector <vector <int>> regions;
map <int, int> dfs(int s, int p) {
    map <int, int> tp;
    tp[col[s]] = 1;
    for (auto i : adj[s]) {
        if (i == p)
            continue;
        auto res = dfs(i, s);
        if (tp.size() < res.size())
            swap(res, tp);
        for (auto j : res)
            tp[j.first] += j.second;
    }
    freq[s] = tp;
    return tp;
}
int main() {
    int n, r, q;
    cin >> n >> r >> q;
    col = vector <int> (n+1);
    adj.resize(n+1);
    regions.resize(r+1);
    freq.resize(n+1);
    cin >> col[1];
    regions[col[1]].push_back(1);
    for (int i = 2; i <= n; i++) {
        int p, c;
        cin >> p >> c;
        adj[i].push_back(p);
        adj[p].push_back(i);
        col[i] = c;
        regions[c].push_back(i);
    }
    dfs(1, 1);
    while (q--) {
        int r1, r2;
        cin >> r1 >> r2;
        int ans = 0;
        for (auto i : regions[r1]) {
            ans += freq[i][r2];
        }
        cout << ans << endl;
    }
}

• Subtask 1: 13 / 15
• Subtask 2: 0 / 85