稀疏数组array

public class Demo08 {
    public static void main(String[] args) {
        //创建一个二维数组5*5
        int[][] array1 = new int[5][5];
        array1[1][2] = 1;
        array1[2][2] = 3;

        //输出原始的数组
        System.out.println("输出原始的数组：");

        for (int[] ints : array1) {
            for (int anInt : ints) {
                System.out.print(anInt + "\t");
            }
            System.out.println();
        }
        System.out.println("=================================");

        //转换成稀疏数组
        //获取有效值个数
        int sum = 0;
        for (int i = 0; i < 5; i++) {
            for (int j = 0; j < 5; j++) {
                if (array1[i][j] != 0) {
                    sum++;
                }
            }
        }
        System.out.println("有效值的个数：" + sum);


        //创建一个稀疏数组的数组
        int[][] array2 = new int[sum + 1][3];
        array2[0][0] = 5;//行
        array2[0][1] = 5;//列
        array2[0][2] = sum;//值

        //遍历二维数组，将非零的值存放在稀疏数组中
        int count = 0;
        for (int i = 0; i < array1.length; i++) {
            for (int j = 0; j < array1[i].length; j++) {
                if (array1[i][j] != 0) {
                    count++;
                    array2[count][0] = i;
                    array2[count][1] = j;
                    array2[count][2] = array1[i][j];
                }
            }
        }
        //输出稀疏数组
        System.out.println("稀疏数组");

        for (int i = 0; i < array2.length; i++) {
            System.out.println(array2[i][0] + "\t"
                    + array2[i][1] + "\t"
                    + array2[i][2] + "\t");
        }
        System.out.println("================================");
        System.out.println("还原数组：");

        //读取稀疏数组
        int[][] array3 = new int[array2[0][0]][array2[0][1]];//数组array2中的行列

        //给其中的元素还原它的值
        for (int i = 1; i < array2.length; i++) {
            array3[array2[i][0]][array2[i][1]] = array2[i][2];
        }

        //打印
        System.out.println("输出还原的数组：");
        for (int[] ints : array3) {
            for (int anInt : ints) {
                System.out.print(anInt + "\t");
            }
            System.out.println();

        }
    }
}