JavaSE 第三十三讲 Java数组常见问题 10.20

public class ArrayTest3
{
    public static void main(String[] args)
    {
        Student[] s = new Student[100];
    
        for(int i = 0; i < s.length; i++)
            {
    
                s[i] = new Student();

                s[i].name = i % 2 == 0 ? "zhangsan" : "lisi";

                /* 等价于上面的三元表达式
                if(i % 2 == 0)
                    {
                        s[i].name = "zhangsan";
                    }
                else
                {
                    s[i].name = "lisi";
                }
                */

            }
    
        for(int i = 0; i < s.length; i++)
        {
            System.out.println(s[i].name);
        }
    }




}

class Student
{
    String name;
}

二维数组：平面的二维结构，本质上是数组的数组。

public class ArrayTest4
{
    public static void main(String[] args)
    {
        /*
        int[][] a = new int[3][];

        a[0] = new int[2];
        a[1] = new int[3];
        a[2] = new int[1];
        */

        int[][] a = new int[][]{{1, 2, 3}, {4}, {5, 6, 7, 8}};
        for(int i = 0; i < a.length; i++)
        {
            for(int j = 0; j < a[i].length; j++)
            {
                System.out.print(a[i][j] + " ");
            }

            System.out.println();
        }
    }
}