public class PaintRound{
/**
* @author Dream_e.
* @version v1.0
*/
private int r;//圆的半径
PaintRound(int r){
this.r = r;
}
public void paint(){
int y = 2*r;//y的最大值为半径的2倍
int x = 0;
int c = 0;
int z = 2;//坐标轴递减量.
for(int j = y; j >= 0; j-=z){
x = getX(r,y);
System.out.print(getSpace(x)+"*");
c = (r-x)*2;
System.out.println(getSpace(c)+"*");
y-=z;
}
}
//计算X坐标.
private int getX(int r, int y){
double temp = Math.sqrt(r*r-(r-y)*(r-y));//根据圆内的正角三角形计算出圆上某点到圆心的X轴距离
int x = (int)Math.round(r-temp);
return x;
}
//计算要打印的空格数量.
private String getSpace(int c){
String space = " ";
for(int i = 0; i < c; i++){
space += " ";
}
return space;
}
public static void main(String[] args){
new PaintRound(10).paint();
}
}