Java基础—数组—16稀疏数组

简单代码实现及还原：（压缩）

代码仅有一个亮点：用数组名.for 打印二维数组

代码需要注意：数组下标越界

public class ArrayDemo {
    public static void main(String[] args) {
        int[][] array1 = new int[11][11];
        array1[1][2] = 1;
        array1[2][3] = 2;
        for (int i = 0; i < 11; i++) {
            for (int j = 0; j < array1.length; j++) {
                System.out.print(array1[i][j] + "\t");
            }
            System.out.println();
        }
        // 计算稀疏数组的大小
        int size = 0;
        for (int i = 0; i < 11; i++) {
            for (int j = 0; j < array1[i].length; j++) {
                if (array1[i][j] != 0) size++;
            }
        }
        System.out.println("稀疏数组========================================");
        int[][] demo = new int[size + 1][3];
        demo[0][0] = 11;
        demo[0][1] = 11;
        int count = 0;
        for (int i = 0; i < 11; i++) {
            for (int j = 0; j < array1[i].length; j++) {
                if (array1[i][j] != 0) {
                    count++;
                    demo[count][0] = i;
                    demo[count][1] = j;
                    demo[count][2] = array1[i][j];
                }
            }
        }
        demo[0][2] = count;
        for (int i = 0; i <= size; i++) {
            for (int i1 = 0; i1 < 3; i1++) {
                System.out.print(demo[i][i1] + "\t");
            }
            System.out.println();
        }
        System.out.println("还原数组========================");
        int[][] array2 = new int[demo[0][0]][demo[0][1]];
        for (int i = 1; i < demo.length; i++) {
            array2[demo[i][0]][demo[i][1]] = demo[i][2];
        }
        // 代码中唯一的亮点：数组名.for打印二维数组
        for (int[] ints : array2) {
            for (int anInt : ints) {
                System.out.print(anInt + "\t");
            }
            System.out.println();
        }
    }
}

代码输出结果：