Submission #913906

#	Time	Username	Problem	Language	Result	Execution time	Memory
913906		VMaksimoski008	Regions (IOI09_regions)	C++14	17 / 100	1322 ms	131072 KiB

regions

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

const int maxn = 2e5 + 5;

void setIO() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

int n, r, q, dp[501][maxn], i;
short home[maxn];
vector<vector<int> > graph;

void dfs(int u) {
    dp[home[u]][u]++;

    for(int &v : graph[u]) {
        dfs(v);
        for(i=1; i<=r; i++)
            dp[i][u] += dp[i][v];
    }
}

int32_t main() {
    setIO();

    cin >> n >> r >> q;
    graph.resize(n+1);

    cin >> home[1];

    for(i=2; i<=n; i++) {
        int p;
        cin >> p >> home[i];
        graph[p].push_back(i);
    }

    if(r <= 500) {
        dfs(1);

        vector<vector<int> > by_home(r+1);
        for(i=1; i<=n; i++)
            by_home[home[i]].push_back(i);

        while(q--) {
            int r1, r2, ans = 0;
            cin >> r1 >> r2;

            for(int &x : by_home[r1])
                ans += dp[r2][x];
        
            cout << ans << '\n';
            cout.flush();
        }
    }


    return 0;
}

• Subtask 1: 12 / 15
• Subtask 2: 5 / 85