数据结构与算法-打印图形算法(圆形)

package *;

/**
 * @program: data-structure
 * @description: 圆形
 * @author: ChenWenLong
 * @create: 2019-09-10 16:08
 **/
public class Circle {

    public static void main(String[] args) {
        circle(60);
    }

    /**
     * 功能描述:
     * 〈指定半径打印圆〉
     *
     * @params : [r]
     * @return : void
     * @author : cwl
     * @date : 2019/9/10 16:11
     */
    public static void circle(int r){
        //y的步长为2,改变y的步长可以将圆形变成椭圆
        for (int y = 0; y <= 2 * r; y += 2) {
            int x = (int)Math.round(r - Math.sqrt(2 * r * y - y * y));
            int len = 2 * (r - x);

            for (int i = 0; i <= x; i++) {
                System.out.print(' ');
            }
            System.out.print('*');

            for (int j = 0; j <= len; j++) {
                System.out.print(' ');
            }
            System.out.println('*');
        }
    }
}