温度转换、计算圆形面积、计算球的体积

public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入华氏温度");

        int F = sc.nextInt();

        double temperature = 5*(F-32)/9.0;
        System.out.printf("温度为%2f",temperature);
    }

计算圆形面积

public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入您要查询的半径");
        int redius = sc.nextInt();
        float area = (float)Math.PI*redius*redius;
        System.out.printf("半径为%d的圆的面积为%f",redius,area);
    }

计算球的体积

/*
输入球的半径，计算球的体积，体积公式：
radius /'reɪdɪəs/ 半径
volume /'vɒljuːm/  体积
 */
public class _03计算球的体积 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println("请输入球的半径");
        int redius = sc.nextInt();
        double volume = 4.0/3*(int)Math.pow(redius,3)*Math.PI;
        System.out.printf("球的半径为%d体积为:%f",redius,volume);
    }
}