java输入半径在控制台用*号绘制圆

java输入半径在控制台用*号绘制圆

import java.util.*;
public class MathRound
{
  private int radius;
  public static void main(String[] args)
  {
    int dist;
    System.out.println("Input the radius(R > 2):");
    Scanner scan = new Scanner(System.in);
    try{
      radius = Integer.parseInt(scan.next());
    }catch(Exception e)
    {
      e.printStackTrace();
    }
    radius = 2*radius;
    System.out.println("===========When R < 20 works well==============");
    for(int i = 0; i <= radius; i ++)
    {
      int j = 0 ;
      if(i == radius/2)//对图形微调
      continue;
      //中垂线到*号的距离
      dist = (int)Math.sqrt(radius*radius - (radius - 2*i)*(radius - 2*i));
      while(j < radius - dist)//左半圆
      {
        System.out.print(" ");
        j++;
      }
      System.out.print("*");
      dist = radius + dist;
      while(j < dist)//右半圆
      {
        System.out.print(" ");
        j ++;
      }
      System.out.println("*");
    }
  }
}
​