import java.util.ArrayList; import java.util.Scanner; import static java.util.Collections.sort; //AC class Pos implements Comparable{ private double x; private double y; public double getX() { return x; } public void setX(double x) { this.x = x; } public double getY() { return y; } public void setY(double y) { this.y = y; } public Pos(){} public Pos(double x, double y) { this.x = x; this.y = y; } @Override public int compareTo(Object o) { if(o instanceof Pos){ Pos p = (Pos) o; if(this.y > p.y){ return 1; }else if(this.y < p.y){ return -1; } return 0; } return 0; } } public class Main_1007 { public static void main(String[] args) { Scanner in = new Scanner((System.in)); int n = in.nextInt(); while(n != 0){ ArrayList<Pos> pos = new ArrayList<>(); for(int i = 1; i <= n; i++){ double x = in.nextDouble(); double y = in.nextDouble(); pos.add(new Pos(x,y)); } //根据y排序 sort(pos); double min = divide(pos,0,pos.size()-1); System.out.println(String.format("%.2f",min)); n = in.nextInt(); } } public static double divide(ArrayList<Pos> pos,int left,int right){ double min = 0; int start = 0,end = 0; if(left >= right){ return Double.MAX_VALUE; } if(left + 1 == right){ min = dist(pos.get(left),pos.get(right)); return min; }else{ int mid = (left + right)/2; double lDist = divide(pos,left,mid); double rDist = divide(pos,mid+1,right); min = lDist < rDist ? lDist : rDist; boolean flag = false; //得到y在[mid.y-min,mid.y+min]的开始下标和结束下标 for(int i = left; i <= right;i++){ if(!flag && (Math.abs(pos.get(mid).getY()-pos.get(i).getY()) < min)){ start = i; flag = true; }else if(flag && (Math.abs(pos.get(mid).getY()-pos.get(i).getY()) >= min)){ end = i; break; } } if(!flag){ return min; } else{ for(int i = start; i < end; i++){ for(int j = i + 1; j < end; j++){ //满足i,j位置的pos对象的X值的距离小于min if( Math.abs(pos.get(i).getX()-pos.get(j).getX())<min){ double result = dist(pos.get(i),pos.get(j)); if(result <min){ min = result; } } } } } } return min; } public static double dist(Pos p1,Pos p2){ return Math.sqrt(Math.pow(p1.getX() - p2.getX(),2) + Math.pow(p1.getY() - p2.getY(),2)) / 2; } }
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