Poj Solution 1939

http://poj.org/problem?id=1939

//* @author: 82638882@163.com
import java.util.*;
public class Main
{
 public static void main(String[] args)
 {
   Scanner in=new Scanner(System.in);
   while(in.hasNext())
   {
    int a=in.nextInt();
    System.out.print(a+" ");
    double x1,y1,x,y,kx,ky;
    x=x1=in.nextDouble();
    y=y1=in.nextDouble();
    for(int i=1;i< a;i++)
    {
      kx=in.nextDouble();
      ky=in.nextDouble();
      System.out.printf("%.6f %.6f ",(x+kx)/2,(y+ky)/2);
      x=kx;
      y=ky;
    }
    System.out.printf("%.6f %.6fn",(x+x1)/2,(y+y1)/2);
      }
  }
}