13-Scanner进阶

package com.wang.scanner;

import java.sql.SQLOutput;
import java.util.Scanner;

public class Demo03 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int i=0;
        float f=0.0F;

        System.out.println("请输入整数");

        if(scanner.hasNextInt()){
            i=scanner.nextInt();
            System.out.println("整数:"+i);
        }else{
            System.out.println("不是整数:");
        }

        System.out.println("请输入小数");

        if(scanner.hasNextFloat()){
            f=scanner.nextFloat();
            System.out.println("小数："+f);
        }else{
            System.out.println("不是小数:");
        }

        scanner.close();
    }
}

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求和平均值

package com.wang.scanner;

import java.util.Scanner;

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

        double sum=0; //和
        int m=0;//计算输入数字数量
        
        //通过循环判断是否还有输入，并在里面进行每一次求和和统计
        while(scanner.hasNextDouble()){
            double x= scanner.nextDouble();
            sum=sum+x;
            m=m+1; //m++    
        }
        
        System.out.println(m+"个数的和是："+sum);
        System.out.println(m+"个数的平均值是："+(sum/m));
        
        scanner.close();
    }
}