結果
| 問題 | No.96 圏外です。 |
| ユーザー |
 ぴろず
|
| 提出日時 | 2014-12-08 20:31:15 |
| 言語 | Java (openjdk 23) |
| 結果 |
AC
|
| 実行時間 | 1,589 ms / 5,000 ms |
| コード長 | 8,864 bytes |
| コンパイル時間 | 2,571 ms |
| コンパイル使用メモリ | 85,928 KB |
| 実行使用メモリ | 74,400 KB |
| 最終ジャッジ日時 | 2024-12-24 07:57:45 |
| 合計ジャッジ時間 | 23,771 ms |
|
ジャッジサーバーID （参考情報） |
judge4 / judge5 |
（要ログイン）
| ファイルパターン | 結果 |
|---|---|
| other | AC * 28 |
ソースコード
import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;import java.util.ArrayList;import java.util.Arrays;import java.util.Comparator;import java.util.HashMap;import java.util.NoSuchElementException;public class Main {public static void main(String[] args) {IO io = new IO();int n = io.nextInt();if (n == 0) {System.out.println(1);return;}Vector2[] r = new Vector2[n];HashMap<Long, Integer> hm = new HashMap<>();for(int i=0;i<n;i++) {int x = io.nextInt();int y = io.nextInt();r[i] = new Vector2(x,y);hm.put(hash(x,y), i);}UnionFind uf = new UnionFind(n);for(int i=0;i<n;i++) {for(int x=-10;x<=10;x++) {for(int y=-10;y<=10;y++) {if (x * x + y * y > 100) {continue;}long hash = hash(r[i].x+x,r[i].y+y);if (hm.containsKey(hash)) {uf.union(i, hm.get(hash));}}}}long maxSq = 0;ArrayList<ArrayList<Integer>> groups = uf.groups();for(ArrayList<Integer> group:groups) {Vector2[] p = new Vector2[group.size()];for(int i=0;i<p.length;i++) {p[i] = r[group.get(i)];}if (p.length <= 2) {for(int i=0;i<p.length;i++) {for(int j=i+1;j<p.length;j++) {maxSq = Math.max(maxSq, p[i].distSquare(p[j]));}}}else{Vector2[] convex = Vector2.convexHull(p);maxSq = Math.max(maxSq, Vector2.convexDiameterSqrt(convex));}}System.out.println(Math.sqrt(maxSq) + 2);}public static long hash(int x,int y) {return (x+10500)*30000+(y+10500);}}class Vector2 {int x = 0;int y = 0;public Vector2(int x,int y) {this.x = x;this.y = y;}public int dot(Vector2 v) {return this.x*v.x+this.y*v.y;}public int cross(Vector2 v) {return this.x*v.y-this.y*v.x;}public Vector2 add(Vector2 v) {return new Vector2(this.x+v.x,this.y+v.y);}public Vector2 subtract(Vector2 v) {return new Vector2(this.x-v.x,this.y-v.y);}public Vector2 multiply(int k) {return new Vector2(k*this.x,k*this.y);}public long normSquare() {return x * x + y * y;}public long distSquare(Vector2 v) {return this.subtract(v).normSquare();}public static boolean intersects(Vector2 p0,Vector2 p1,Vector2 p2,Vector2 p3) {Vector2 v1 = p1.subtract(p0);Vector2 v2 = p3.subtract(p2);Vector2 v = p2.subtract(p0);Vector2 v_ = p2.subtract(p1);int a = v1.cross(v2);if(a==0) {return v.cross(v_) == 0 && (v.dot(v_) <= 0 || p0.subtract(p2).dot(p0.subtract(p3)) <= 0);}else{int a1 = -v1.cross(v);int a2 = -v2.cross(v);if (a>0) {return (0<=a1&&a1<=a&&0<=a2&&a2<=a);}else{return (a<=a1&&a1<=0&&a<=a2&&a2<=0);}}}public static Vector2[] convexHull(Vector2[] p) {int n = p.length;int k = 0;Arrays.sort(p,new LexicographicalComp());Vector2[] q = new Vector2[n*2];for(int i=0;i<n;q[k++]=p[i++]) {while(k >= 2 && q[k-2].subtract(q[k-1]).cross(q[k-1].subtract(p[i])) <= 0) {k--;}}for(int i=n-2, t=k+1;i>=0;q[k++]=p[i--]) {while(k >= t && q[k-2].subtract(q[k-1]).cross(q[k-1].subtract(p[i])) <= 0) {k--;}}return Arrays.copyOf(q, k-1);}public static long convexDiameterSqrt(Vector2[] convex) {int n = convex.length;int is = 0, js = 0;for(int i=1; i<n; i++) {if (convex[i].y > convex[is].y) {is = i;}if (convex[i].y <= convex[js].y) {js = i;}}long maxd = convex[is].distSquare(convex[js]);int i, j; //maxi, maxji = is; //maxi = is;j = js; //maxj = js;do {Vector2 vi = convex[i];Vector2 vid = convex[(i+1)%n].subtract(vi);Vector2 vj = convex[j];Vector2 vjd = convex[(j+1)%n].subtract(vj);//System.out.println(is + "," + js + ";" + i + "," + j + ";" + vi + "," + vj + ";" + vid + "," + vjd);if (vid.cross(vjd) >= 0) {j = (j+1)%n;}else{i = (i+1)%n;}long dist = vi.distSquare(vj);if (dist > maxd) {maxd = dist;//maxi = i; maxj = j;}} while (i != is || j != js);return maxd;}public String toString() {return this.x + " " + this.y;}public static class LexicographicalComp implements Comparator<Vector2>{public int compare(Vector2 o1, Vector2 o2) {if (o1.x != o2.x) {return Integer.compare(o1.x, o2.x);}return Integer.compare(o1.y, o2.y);}}}class UnionFind {private int[] data;public UnionFind(int size) {data = new int[size];Arrays.fill(data, -1);}public void union(int x,int y) {x = root(x);y = root(y);if (x!=y) {if (data[y] < data[x]) {int tmp = y;y = x;x = tmp;}data[x] += data[y];data[y] = x;}}public boolean isConnected(int x,int y) {return root(x)==root(y);}private int root(int x) {return data[x] < 0 ? x : (data[x] = root(data[x]));}public int size(int x) {return -data[root(x)];}public ArrayList<ArrayList<Integer>> groups() {int n = data.length;ArrayList<ArrayList<Integer>> g = new ArrayList<ArrayList<Integer>>();HashMap<Integer,Integer> hm = new HashMap<Integer, Integer>();for(int i=0;i<n;i++) {int r = root(i);if (!hm.containsKey(r)) {hm.put(r, g.size());g.add(new ArrayList<Integer>());}g.get(hm.get(r)).add(i);}return g;}public String toString() {return Arrays.toString(data);}}class IO {private final InputStream in;private final PrintWriter out = new PrintWriter(System.out);private final byte[] buffer = new byte[1024];private int ptr = 0;private int buflen = 0;public IO() { this(System.in);}public IO(InputStream source) { this.in = source;}private boolean hasNextByte() {if (ptr < buflen) {return true;}else{ptr = 0;try {buflen = in.read(buffer);} catch (IOException e) {e.printStackTrace();}if (buflen <= 0) {return false;}}return true;}private int readByte() { if (hasNextByte()) return buffer[ptr++]; else return -1;}private static boolean isPrintableChar(int c) { return 33 <= c && c <= 126;}private static boolean isNewLine(int c) { return c == '\n' || c == '\r';}private void skipUnprintable() { while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;}private void skipNewLine() { while(hasNextByte() && isNewLine(buffer[ptr])) ptr++;}public boolean hasNext() { skipUnprintable(); return hasNextByte();}public boolean hasNextLine() { skipNewLine(); return hasNextByte();}public String next() {if (!hasNext()) {throw new NoSuchElementException();}StringBuilder sb = new StringBuilder();int b = readByte();while(isPrintableChar(b)) {sb.appendCodePoint(b);b = readByte();}return sb.toString();}public String nextLine() {if (!hasNextLine()) {throw new NoSuchElementException();}StringBuilder sb = new StringBuilder();int b = readByte();while(!isNewLine(b)) {sb.appendCodePoint(b);b = readByte();}return sb.toString();}public long nextLong() {if (!hasNext()) {throw new NoSuchElementException();}long n = 0;boolean minus = false;int b = readByte();if (b == '-') {minus = true;b = readByte();}while(true){if ('0' <= b && b <= '9') {n *= 10;n += b - '0';}else{return minus ? -n : n;}b = readByte();}}public int nextInt() {long nl = nextLong();if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE) {throw new NumberFormatException();}return (int) nl;}public char nextChar() {if (!hasNext()) {throw new NoSuchElementException();}return (char) readByte();}public double nextDouble() { return Double.parseDouble(next());}public int[] arrayInt(int n) { int[] a = new int[n]; for(int i=0;i<n;i++) a[i] = nextInt(); return a;};public long[] arrayLong(int n) { long[] a = new long[n]; for(int i=0;i<n;i++) a[i] = nextLong(); return a;};public double[] arrayDouble(int n) { double[] a = new double[n]; for(int i=0;i<n;i++) a[i] = nextDouble(); return a;};public void arrayInt(int[]... a) {for(int i=0;i<a[0].length;i++) {for(int j=0;j<a.length;j++) {a[j][i] = nextInt();}}}public void println(long x) { out.println(x);}public void println(double x) { out.println(x);}public void println(String s) { out.println(s);}public void println() { out.println(); }public void print(long x) { out.print(x); }public void print(double x) { out.print(x); }public void print(String s) { out.print(s); }public void print(char c) {out.print(c);}public void flush() {out.flush(); }}