挑战程序竞赛系列（87）：3.6平面扫描（1）

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.StringTokenizer;
import java.util.TreeSet;

public class Main{

    String INPUT = "./data/judge/201709/P2932.txt";

    public static void main(String[] args) throws IOException {
        new Main().run();
    }

    static final int MAX_N = 40000 + 16;

    class E implements Comparable<E>{

        double x;
        int id;

        E(double x, int id){
            this.x  = x;
            this.id = id;
        }

        @Override
        public int compareTo(E o) {
            return Double.compare(x, o.x);
        }

        @Override
        public boolean equals(Object obj) {
            return compareTo((E)(obj)) == 0;
        }
    }

    class C{

        double x;
        double y;
        double r;

        C(double r, double x, double y){
            this.x = x;
            this.y = y;
            this.r = r;
        }
    }

    int N;
    C[] cs = new C[MAX_N];
    E[] xs = new E[2 * MAX_N];

    // j 是否包含于 i
    boolean inside(int i, int j) {
        double dx = cs[i].x - cs[j].x;
        double dy = cs[i].y - cs[j].y;
        return dx * dx + dy * dy <= cs[i].r * cs[i].r;
    }

    void solve() {

        for (int i = 0; i < N; ++i) {
            C c = cs[i];
            xs[2 * i]     = new E(c.x - c.r, i);
            xs[2 * i + 1] = new E(c.x + c.r, i + N);
        }

        Arrays.sort(xs, 0, 2 * N);

        TreeSet<E> set = new TreeSet<E>();
        List<Integer> ans = new ArrayList<Integer>();
        for (int i = 0; i < 2 * N; ++i) {
            E e = xs[i];
            int id = e.id % N;
            E crtC = new E(cs[id].y, id);
            if (e.id < N) {
                E up = set.ceiling(crtC);
                E dn = set.floor(crtC);
                if (up != null && inside(up.id, id)) continue;
                if (dn != null && inside(dn.id, id)) continue;
                ans.add(id);
                set.add(crtC);
            }
            else {
                set.remove(crtC);
            }
        }

        Collections.sort(ans);
        out.println(ans.size());
        for (int i = 0; i < ans.size(); ++i) {
            out.print((ans.get(i) + 1) + (i + 1 == ans.size() ? "\n" : " "));
        }
    }

    void read() {
        N = ni();
        for (int i = 0; i < N; ++i) {
            cs[i] = new C(nd(), nd(), nd());
        }
        solve();
    }

    FastScanner in;
    PrintWriter out;

    void run() throws IOException {
        boolean oj;
        try {
            oj = ! System.getProperty("user.dir").equals("F:\\java_workspace\\leetcode");
        } catch (Exception e) {
            oj = System.getProperty("ONLINE_JUDGE") != null;
        }

        InputStream is = oj ? System.in : new FileInputStream(new File(INPUT));
        in = new FastScanner(is);
        out = new PrintWriter(System.out);
        long s = System.currentTimeMillis();
        read();
        out.flush();
        if (!oj){
            System.out.println("[" + (System.currentTimeMillis() - s) + "ms]");
        }
    }

    public boolean more(){
        return in.hasNext();
    }

    public int ni(){
        return in.nextInt();
    }

    public long nl(){
        return in.nextLong();
    }

    public double nd(){
        return in.nextDouble();
    }

    public String ns(){
        return in.nextString();
    }

    public char nc(){
        return in.nextChar();
    }

    class FastScanner {
        BufferedReader br;
        StringTokenizer st;
        boolean hasNext;

        public FastScanner(InputStream is) throws IOException {
            br = new BufferedReader(new InputStreamReader(is));
            hasNext = true;
        }

        public String nextToken() {
            while (st == null || !st.hasMoreTokens()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (Exception e) {
                    hasNext = false;
                    return "##";
                }
            }
            return st.nextToken();
        }

        String next = null;
        public boolean hasNext(){
            next = nextToken();
            return hasNext;
        }

        public int nextInt() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Integer.parseInt(more);
        }

        public long nextLong() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Long.parseLong(more);
        }

        public double nextDouble() {
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return Double.parseDouble(more);
        }

        public String nextString(){
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return more;
        }

        public char nextChar(){
            if (next == null){
                hasNext();
            }
            String more = next;
            next = null;
            return more.charAt(0);
        }
    }
}