Question

通过math类方法,打印出一个近似圆

Answer 1

import java.lang.Math;

public class FirstProject {

public static void main(String[] args) {

paint(40); //半径40

}

public static void paint(int r) {

//假定圆心在坐标(r,r);

int y = r * 2; //y的坐标开始

int x = 0;

int c = 0; //中间空格数量

int z = 2; //每行递减量

for (int j = r * 2; j >= 0; j=j-z) {

x = getX(r,y);

System.out.print(getSpace(x) + "*");

c = (r-x)*2;

System.out.println(getSpace(c) + "*");

y-=z;

}

}

public static int getX(int r,int y) {

//解圆标准方程的

int x = y - r;

double t = Math.sqrt((r * r) - (x * x));

return (int) Math.round(r-t);

}

public static String getSpace(int i) {

String s = "";

for (int j = 0; j < i; j++) {

s += " ";

}

return s;

}

}