Java_基础语法编程练习

public static void main(String[] args) {
        int sum = 0;
        for(int i = 0 ;i < 100 ;i++) {
            int n = (int) (Math.random()*101);
            sum += n;
        }
        System.out.println("平均值为:" + (sum/100.0));
    }

public static void main(String[] args) throws MyException {
        System.out.println("请输入一个大于100小于1000的三位整数:");
        Scanner sc = new Scanner(System.in);
        int input = sc.nextInt();
        if(input < 100 || input > 1000) {
            throw new MyException();//自定义异常类,判断输入的数据是否满足条件
        }
        int a = input / 100;
        int b = input / 10 % 10;
        int c = input % 10;
        if (input == a * a * a + b * b * b + c * c * c) {
            System.out.print(input + "是水仙花数" + "\n" + input + "=" + (a + "*" + a +"*"+ a) + "+" +(b+ "*"+ b +"*" +b) +"+"+ (c +"*"+ c +"*"+ c));
        } else
            System.out.print(input + "不是水仙花数");

    }

public static void main(String[] args) {
        //从键盘接收数据
        System.out.println("请输入一个整数:");
        Scanner s = new Scanner(System.in);
        int x = s.nextInt();
        int a = x % 2;
        if(a != 0) {
            System.out.println(x + "是奇数");
        }
        else {
            System.out.println(x + "是偶数");
        }
    }

public static void main(String[] args) {
        //升学考试问题:英语,数学C语言三门总成绩大于等于230,并且英语成绩大于等于60
        //才能升学
        System.out.print("请输入你的英语成绩:");
        Scanner english = new Scanner(System.in);
        double x = english.nextDouble();
        
        System.out.print("请输入你的数学成绩:");
        Scanner math = new Scanner(System.in);
        double y = english.nextDouble();
        
        System.out.print("请输入你的C语言成绩:");
        Scanner cEnglish = new Scanner(System.in);
        double z = cEnglish.nextDouble();
        //三门课程总成绩
        double sum = x + y + z;
        System.out.println("英语成绩为" + x);
        System.out.println("三门课程总成绩" + sum);
        
        if(x >= 60 && sum >= 230) {
                System.out.println("恭喜你!成功升学!!");
        }else {
            System.out.println("很遗憾!你还需要加油哦!!");
        }
    }

public static void main(String[] args) {
        //输入一个数,判断是否能被3整出,并输出相应的提示信息
        System.out.print("请输入一个数:");
        Scanner a = new Scanner(System.in);
        double x = a.nextDouble();
        
        if((x % 3) == 0) {
            System.out.println(x + "能被3整除");
        }else {
            System.out.println(x + "不能被3整除");
        }
    }

public static void main(String[] args) {
        //判断两个数的最大值并输出
        System.out.print("请输入第一个数:");
        Scanner a = new Scanner(System.in);
        double x = a.nextDouble();
        
        System.out.print("请输入第二个数:");
        Scanner b = new Scanner(System.in);
        double y = b.nextDouble();
        //三目运算符
        double z = (x > y)?x:y;
        System.out.println("两个数的最大值为:" + z);
    }

public static void main(String[] args) {
        //用if-else语句判断输入的年份是否为闰年
        //能被4整除但不能被100整除的年份,或者能被400整除的年份
        System.out.print("请输入一个年份:");
        Scanner sc = new Scanner(System.in);
        int year = sc.nextInt();
        
        if(((year % 4 ==0) && ((year & 100) != 0))||(year % 400 == 0)) {
            System.out.println(year + "是闰年");
        }else {
            System.out.println(year + "不是闰年");
        }
    }

public static void main(String[] args) {
        //键盘输入1-7的任意数字,分别输出对应的信息
        System.out.print("请输入1-7的任意数字:");
        Scanner sc = new Scanner(System.in);
        int week = sc.nextInt();
        
        switch(week) {
        case 1:
            System.out.println("今天是星期一");
            break;
        case 2:
            System.out.println("今天是星期二");
            break;
        case 3:
            System.out.println("今天是星期三");
            break;
        case 4:
            System.out.println("今天是星期四");
            break;
        case 5:
            System.out.println("今天是星期五");
            break;
        case 6:
            System.out.println("今天是星期六");
            break;
        case 7:
            System.out.println("今天是星期日");
            break;
        default:
            System.out.println("您输入的数字是无效的");
        }
        sc.close();
    }