稀疏数组 - 二维数组转稀疏数组

public class SparseArray {
    public static void main(String[] args) {
        // 定义一个二维数组
        int[][] originArray = initOriginArray();
        System.out.println("======================二维数组======================");
        for (int[] row : originArray) {
            for (int data : row) {
                System.out.printf("%d\t", data);
            }
            System.out.println();
        }
        // 二维数组转稀疏数组
        int[][] sparseArray = transToSparseArray(originArray);
        System.out.println("======================稀疏数组======================");
        for (int[] row : sparseArray) {
            for (int data : row) {
                System.out.printf("%d\t", data);
            }
            System.out.println();
        }
    }

    private static int[][] transToSparseArray(int[][] originArray) {
        // 1. 获取二维数组有多少个值
        int sum = getSum(originArray);
        // 2. 创建稀疏数组
        int[][] sparseArray = initSparseArray(sum, originArray);
        // 3. 给稀疏数组赋值
        assembleSparseArray(sparseArray, originArray);
        return sparseArray;
    }

    private static void assembleSparseArray(int[][] sparseArray, int[][] originArray) {
        int count = 0;
        int row = originArray.length;
        int col = originArray[0].length;
        for (int i = 0; i < row; i++) {
            for (int j = 0; j < col; j++) {
                if (originArray[i][j] != 0) {
                    count++;
                    sparseArray[count][0] = i;
                    sparseArray[count][1] = j;
                    sparseArray[count][2] = originArray[i][j];
                }
            }
        }
    }

    private static int[][] initSparseArray(int sum, int[][] originArray) {
        int[][] sparseArray = new int[sum + 1][3];
        sparseArray[0][0] = originArray.length;
        sparseArray[0][1] = originArray[0].length;
        sparseArray[0][2] = sum;
        return sparseArray;
    }

    private static int getSum(int[][] originArray) {
        int sum = 0;
        int row = originArray.length;
        int col = originArray[0].length;
        for (int i = 0; i < row; i++) {
            for (int j = 0; j < col; j++) {
                if (originArray[i][j] != 0) {
                    sum++;
                }
            }
        }
        return sum;
    }

    private static int[][] initOriginArray() {
        int[][] originArray = new int[11][11];
        originArray[1][2] = 1;
        originArray[2][3] = 2;
        originArray[3][4] = 3;
        originArray[4][5] = 4;
        originArray[5][6] = 5;
        originArray[6][7] = 6;
        return originArray;
    }
}

　　

======================二维数组======================
0	0	0	0	0	0	0	0	0	0	0	
0	0	1	0	0	0	0	0	0	0	0	
0	0	0	2	0	0	0	0	0	0	0	
0	0	0	0	3	0	0	0	0	0	0	
0	0	0	0	0	4	0	0	0	0	0	
0	0	0	0	0	0	5	0	0	0	0	
0	0	0	0	0	0	0	6	0	0	0	
0	0	0	0	0	0	0	0	0	0	0	
0	0	0	0	0	0	0	0	0	0	0	
0	0	0	0	0	0	0	0	0	0	0	
0	0	0	0	0	0	0	0	0	0	0	
======================稀疏数组======================
11	11	6	
1	2	1	
2	3	2	
3	4	3	
4	5	4	
5	6	5	
6	7	6	

Process finished with exit code 0