一、数组

数组可以存放多个同一类型的数据。数组也是一种数据类型，是引用类型。

一个养鸡场有6只鸡，它们的体重分别是3kg, 5kg,1kg,3.4kg,2kg.50kg。请问这六5 R鸡的总体重是多少?平均体重是多少?

普通方法解决:

package com.jun.demo01;

public class demo01 {
    public static void main(String[] args) {
        double chicken1 = 3;
        double chicken2 = 5;
        double chicken3 = 1;
        double chicken4 = 3.4;
        double chicken5 = 2;
        double chicken6 = 50;
        double and = chicken1 + chicken2 + chicken3 + chicken4 + chicken5 + chicken6;
        System.out.println("六只鸡的总体重为：" + and + "kg");
        double average = and / 6;
        System.out.println("六只鸡的平均体重为：" + average + "kg");
    }
}

使用数组解决:

package com.jun.demo01;

public class demo02 {
    public static void main(String[] args) {
        //定义一个数组保存鸡的体重
        double[] chicken = {3,5,1,3.4,2,50};
        //定义一个变量用于接收总体重
        double and = 0;
        //遍历数组
        for (int i = 0; i < chicken.length ; i++) {
           // System.out.println("第"+ (i+1) + "鸡的体重为:" + chicken[i] + "kg");
            and += chicken[i];
        }
        System.out.println("六只鸡的总体重为:" + and + "kg");
        System.out.println("六只鸡的平均体重为:" + and / chicken.length + "kg");
    }
}

二、入门练习

package com.jun.demo01;

import java.util.Scanner;

public class demo03 {
    public static void main(String[] args) {
        double scores[] = new double[5];
        Scanner scanner = new Scanner(System.in);
        //循环输入数据
        for (int i = 0; i < scores.length ; i++) {
            System.out.println("请输入第"+ (i + 1) + "个元素");
            scores[i] = scanner.nextDouble();
        }
        for (int i = 0; i < scores.length ; i++) {
            System.out.println("数组的第" + (i + 1) + "值为:"+ scores[i]);
        }
    }
}