Submission #651488

#	Time	Username	Problem	Language	Result	Execution time	Memory
651488		tanprodium	Regions (IOI09_regions)	C++14	95 / 100	8068 ms	50452 KiB

regions

#include<bits/stdc++.h>

using namespace std;

using pii = pair<int, int>;

struct Queries {
    int r1, r2;

    Queries() {}
    Queries(int _r1, int _r2): r1(_r1), r2(_r2) {}
};

const int N = 2e5 + 5;
const int R = 25 * 1e3 + 5;

Queries qr[N];
vector<int> id[R], reg[R], adj[N], e[R];
map<pii, int> save;
map<pii, bool> exist;
int l[N], r[N];
int cnt;

void dfs(int fa, int u) {
    l[u] = ++cnt;

    for (int v : adj[u])
    if (v != fa)
        dfs(u, v);

    r[u] = cnt;
}

void solve() {
    int n, regs, q;
    cin >> n >> regs >> q;

    int x;
    cin >> x;
    reg[x].push_back(1);

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

    cnt = 0;
    dfs(0, 1);

    for (int i = 1; i <= regs; i++) {
        for (int x : reg[i]) {
            e[i].push_back(l[x]);
        }
    }

    for (int i = 1; i <= regs; i++)
        sort(e[i].begin(), e[i].end());

    for (int i = 1; i <= q; i++) {
        int r1, r2;
        cin >> r1 >> r2;

        if (exist[{r1, r2}]) {
            cout << save[{r1, r2}] << endl;
            fflush(stdout);
        }
        else {

        int ans = 0;

        for (int x : reg[r1]) {
            int u = lower_bound(e[r2].begin(), e[r2].end(), l[x]) - e[r2].begin();
            int v = upper_bound(e[r2].begin(), e[r2].end(), r[x]) - e[r2].begin();
            ans += 1ll * (v - u);
        }

        exist[{r1, r2}] = true;
        save[{r1, r2}] = ans;

        cout << ans << endl;
        fflush(stdout);
        }
    }
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    solve();
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 80 / 85