Submission #867751

#	Time	Username	Problem	Language	Result	Execution time	Memory
867751		overwatch9	Regions (IOI09_regions)	C++17	30 / 100	3640 ms	131072 KiB

regions

#include <iostream>
#include <vector>
#include <algorithm>
#include <map>
using namespace std;
vector <vector <int>> adj;
vector <int> col;
vector <vector <int>> ans;
vector <vector <int>> freq, regions;
int n, r, q;
void dfs(int s, int p) {
    freq[s][col[s]]++;
    for (auto i : adj[s]) {
        if (i == p)
            continue;
        dfs(i, s);
        for (int j = 1; j <= r; j++)
            freq[s][j] += freq[i][j];
    }
}
int main() {
    cin >> n >> r >> q;
    col = vector <int> (n+1);
    adj.resize(n+1);
    ans.resize(n+1);
    freq = vector <vector <int>> (n+1, vector <int> (r+1));
    regions.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[col[i]].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 << '\n';
    }
}

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