【Java】稀疏矩阵

public class SparesArray {
    public static void main(String[] args) {
        // 创建一个二维数组 11*11  0：没有旗子， 1：黑棋， 2：白棋
        int[][] array1 = new int[11][11];
        array1[1][2] = 1;
        array1[2][3] = 2;

        System.out.println("输出原始的矩阵");

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

        // 转换为稀疏数组
        // 1. 获取有效值的个数
        int sum = 0;
        for (int i = 0; i < 11; i++){
            for (int j = 0; j < 11; j++) {
                if (array1[i][j] != 0) {
                    sum++;
                }
            }
        }
        System.out.println("有效值个数：" + sum);

        // 2. 创建一个稀疏数组的数组
        int[][] array2 = new int[sum+1][3];
        array2[0][0] = 11;
        array2[0][1] = 11;
        array2[0][2] = sum;

        // 遍历二维数组，将非零值放入稀疏数组
        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];
                }
            }
        }

        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]);
        }

        // ===============================================================
        // 稀疏数组还原
        System.out.println("还原");

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

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

        // 3. 打印
        for (int[] ints : array3){
            for (int anInt : ints){
                System.out.print(anInt + "\t");
            }
            System.out.println();
        }

    }
}