Scanner-Demo04-05

package com.kuang.scanner;

import java.util.Scanner;
//=====================
//Demo04
//=====================
public class Demo04 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);


        //从键盘接受数据
        int i = 0;
        float f = 0.0f;

        System.out.println("请输入整数:  ");


        //如果..那么
        if (scanner.hasNextInt()){
            i = scanner.nextInt();
            System.out.println("整数数据: "+ i);
        }else{
            System.out.println("输入的不是整数数据!");
        }

        //如果..那么
        System.out.println("请输入小数:  ");


        if (scanner.hasNextFloat()){
            f = scanner.nextFloat();
            System.out.println("小数数据: "+ f);
        }else{
            System.out.println("输入的不是小数数据!");
        }




        scanner.close();
    }
}

package com.kuang.scanner;

import java.util.Scanner;
//=====================
//Demo05
//=====================
public class Demo05 {
    public static void main(String[] args) {
        //我们可以输入多个数字, 并求其总和平均数, 每输入一个数字用回车确认, 通过输入非数字来结束输入并输出执行结果;


        Scanner scanner = new Scanner(System.in);


        //和
        double sum = 0;
        //计算输入了多少个数字
        int m = 0;

        System.out.println("请输入数据:");
        //通过循环判断是否还有输入, 并在里面对每一次进行求和与统计
        while (scanner.hasNextDouble()){
            double x = scanner.nextDouble();
            m = m + 1;  //m++
            sum = sum + x;
            System.out.println("你输入了第"+m+"个数据, 然后当前结果sum="+sum);

        }

        System.out.println(m + "个数的和为" + sum);
        System.out.println(m + "个数的平均值是" + (sum / m));





        scanner.close();
    }
}

标签：scanner,05,sum,System,Scanner,Demo04,println,输入,out
来源： https://www.cnblogs.com/iamaghao/p/15312600.html