Submission #872142

#	Time	Username	Problem	Language	Result	Execution time	Memory
872142		overwatch9	Regions (IOI09_regions)	C++17	15 / 100	8096 ms	76044 KiB

regions

#include <iostream>
#include <vector>
#include <unordered_map>
using namespace std;
struct stree {
    #define lc v*2
    #define rc v*2+1
    vector <unordered_map <int, int>> tree;
    stree (int s) {
        tree.resize(s * 4);
    }
    void pushup(int v) {
        if (tree[rc].size() < tree[lc].size()) {
            tree[v] = tree[lc];
            for (auto i : tree[rc])
                tree[v][i.first] += i.second;
        } else {
            tree[v] = tree[rc];
            for (auto i : tree[lc])
                tree[v][i.first] += i.second;
        }
    }
    void update(int v, int tl, int tr, int p, int val) {
        if (tl > p || tr < p)
            return;
        if (tl == tr) {
            tree[v][val]++;
            return;
        }
        int tm = (tl + tr) / 2;
        update(lc, tl, tm, p, val);
        update(rc, tm+1, tr, p, val);
        pushup(v);
    }
    int query(int v, int tl, int tr, int l, int r, int val) {
        if (tl > r || tr < l)
            return 0;
        if (tl >= l && tr <= r) {
            if (tree[v].find(val) != tree[v].end())
                return tree[v][val];
            return 0;
        }
        int tm = (tl + tr) / 2;
        int a = query(lc, tl, tm, l, r, val);
        int b = query(rc, tm+1, tr, l, r, val);
        return a + b;
    }
};
const int maxn = 2e5;
int visit[maxn], finish[maxn], region[maxn];
vector <int> adj[maxn];
int t = 0;
void dfs(int s, int p) {
    visit[s] = t++;
    for (auto i : adj[s])
        dfs(i, s);
    finish[s] = t;
}
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    int n, r, q;
    cin >> n >> r >> q;
    vector <vector <int>> cities(r+1);
    cin >> region[1];
    cities[region[1]].push_back(1);
    for (int i = 2; i <= n; i++) {
        int x;
        cin >> x;
        adj[x].push_back(i);
        cin >> region[i];
        cities[region[i]].push_back(i);
    }
    dfs(1, 1);
    stree tree(t+1);
    for (int i = 1; i <= n; i++)
        tree.update(1, 0, t, visit[i], region[i]);
    while (q--) {
        int r1, r2;
        cin >> r1 >> r2;
        int ans = 0;
        for (auto i : cities[r1]) {
            ans += tree.query(1, 0, t, visit[i], finish[i]-1, r2);
        }
        cout << ans << endl;
    }
}

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