[数据结构与算法]稀疏数组的实现(尚硅谷Java数据结构与算法)

整个代码放在main函数中就可以运行

从数组---->稀疏数组

int arrays[][] = new int[11][11];
        arrays[1][2] = 1;
        arrays[2][3] = 2;
        //打印初始化的数组
        for (int i = 0;i<arrays.length;i++){
            for (int j = 0;j<arrays[i].length;j++){
                System.out.print(arrays[i][j]);
            }
            System.out.println();
        }
        int sum = 0;
        for (int i = 0;i<arrays.length;i++){
            for (int j = 0;j<arrays[i].length;j++){
                if(arrays[i][j] != 0)
                    sum++;
            }
        }
        //得到稀疏数组
        int array[][] = new int[sum+1][3];
        array[0][0] = arrays.length;
        array[0][1] = arrays[0].length;
        array[0][2] = sum;
        int k=1;

        for (int i = 0;i<arrays.length;i++){
            for (int j = 0;j<arrays[i].length;j++){
                if(arrays[i][j] != 0) {
                    array[k][0] = i;
                    array[k][1] = j;
                    array[k][2] = arrays[i][j];
                    k++;
                    }
                }
            }

        //打印稀疏数组
        System.out.println("打印稀疏数组");
        for (int i = 0;i<array.length;i++){
            for (int j = 0;j<array[i].length;j++){
                System.out.print(array[i][j]+"\t");
            }
            System.out.println();
        }

从稀疏数组----->原数组

//由稀疏数组恢复原数组
        int rows = array[0][0];
        int column = array[0][1];
        int arryRecovery[][] = new int[rows][column];
        for (int i = 1; i < array.length; i++) {
            arryRecovery[array[i][0]][array[i][1]] = array[i][2];
        }

        //打印恢复的数组
        System.out.println("打印恢复的数组");
        for (int i = 0;i<arryRecovery.length;i++){
            for (int j = 0;j<arryRecovery[i].length;j++){
                System.out.print(arryRecovery[i][j]);
            }
            System.out.println();
        }