Submission #1157178

#	Time	Username	Problem	Language	Result	Execution time	Memory
1157178		OI_Account	Circle selection (APIO18_circle_selection)	C++17	7 / 100	3116 ms	609468 KiB

circle_selection

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

typedef long long ll;

const int N = 1'000'000;

int n, x[N + 10], y[N + 10], r[N + 10];
int ans[N + 10], id[N + 10], sizeVecX;
int mark[N + 10], cnt[N + 10];
vector<int> vecX, vec;
set<pair<int, int>> s[4 * N + 10];
pair<int, int> p[N + 10];

void readInput() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> x[i] >> y[i] >> r[i];
        p[i] = {-r[i], i};
    }
}

void calcId() {
    sort(p + 1, p + n + 1);
    for (int i = 1; i <= n; i++)
        id[i] = p[i].second;
}

void calcVecX() {
    for (int i = 1; i <= n; i++) {
        vecX.push_back(x[i] - r[i]);
        vecX.push_back(x[i] + r[i]);
    }
    sort(vecX.begin(), vecX.end());
    vecX.resize(unique(vecX.begin(), vecX.end()) - vecX.begin());
    sizeVecX = (int) vecX.size();
}

int getIdx(int x) {
    return lower_bound(vecX.begin(), vecX.end(), x) - vecX.begin();
}

void update(int idx, pair<int, int> p, int d, int id = 1, int l = 0, int r = sizeVecX) {
    if (idx < l || r <= idx)
        return;
    if (d == 1)
        s[id].insert(p);
    else
        s[id].erase(p);
    if (l + 1 == r)
        return;
    int mid = (l + r) >> 1;
    update(idx, p, d, id << 1, l, mid);
    update(idx, p, d, id << 1 | 1, mid, r);
}

void changePoint(int idx, int d) {
    for (int i = -1; i <= 1; i += 2)
        for (int j = -1; j <= 1; j += 2) {
            int nx = x[idx] + r[idx] * i;
            int ny = y[idx] + r[idx] * j;
            update(getIdx(nx), {ny, idx}, d);
        }
}

void build() {
    for (int i = 1; i <= n; i++)
        changePoint(i, 1);
}

void check(int id, int l, int r) {
    auto au = s[id].lower_bound({l, 0});
    while (au != s[id].end() && au -> first <= r) {
        vec.push_back(au -> second);
        au++;
    }
}

void get(int st, int en, int x, int y, int id = 1, int l = 0, int r = sizeVecX) {
    if (en <= l || r <= st)
        return;
    if (st <= l && r <= en) {
        check(id, x, y);
        return;
    }
    int mid = (l + r) >> 1;
    get(st, en, x, y, id << 1, l, mid);
    get(st, en, x, y, id << 1 | 1, mid, r);
}

bool isGood(int i, int j) {
    ll dx = x[i] - x[j], dy = y[i] - y[j];
    return dx * dx + dy * dy <= (ll) (r[i] + r[j]) * (r[i] + r[j]) ;
}

void newPoint(int idx) {
    vec.clear();
    get(getIdx(x[idx] - r[idx]), getIdx(x[idx] + r[idx]) + 1, y[idx] - r[idx], y[idx] + r[idx]);
    for (auto x: vec)
        if (!mark[x]) {
            if (isGood(x, idx)) {
                ans[x] = idx;
                changePoint(x, -1);
            }
            mark[x] = true;
            cnt[x]++;
        }
    for (auto x: vec)
        mark[x] = false;
}

void solve() {
    for (int i = 1; i <= n; i++)
        if (!ans[id[i]])
            newPoint(id[i]);
}

void writeOutput() {
    for (int i = 1; i <= n; i++)
        cout << ans[i] << ' ';
    cout.flush();
}

int main() {
    ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    readInput();
    calcId();
    calcVecX();
    build();
    solve();
    writeOutput();
    return 0;
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 12
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 30
• Subtask 6: 0 / 13