How to print Two-Dimensional Array like table

Question

I\'m having a problem with two dimensional array. I\'m having a display like this:

1 2 3 4 5 6 7 9 10 11 12 13 14 15 16 . . . etc

What basi

Answer 1

You can creat a method that prints the matrix as a table :

Note: That does not work well on matrices with numbers with many digits and non-square matrices.

    public static void printMatrix(int size,int row,int[][] matrix){

            for(int i = 0;i <  7 * size ;i++){ 
                  System.out.print("-");    
            }
                 System.out.println("-");

            for(int i = 1;i <= matrix[row].length;i++){
               System.out.printf("| %4d ",matrix[row][i - 1]);
             }
               System.out.println("|");


                 if(row == size -  1){

             // when we reach the last row,
             // print bottom line "---------"

                    for(int i = 0;i <  7 * size ;i++){ 
                          System.out.print("-");
                     }
                          System.out.println("-");

                  }
   }

  public static void main(String[] args){

     int[][] matrix = {

              {1,2,3,4},
              {5,6,7,8},
              {9,10,11,12},
              {13,14,15,16}


      };

       // print the elements of each row:

     int rowsLength = matrix.length;

          for(int k = 0; k < rowsLength; k++){

              printMatrix(rowsLength,k,matrix);
          }


  }

Output :

---------------------
|  1 |  2 |  3 |  4 |
---------------------
|  5 |  6 |  7 |  8 |
---------------------
|  9 | 10 | 11 | 12 |
---------------------
| 13 | 14 | 15 | 16 |
---------------------

I created this method while practicing loops and arrays, I'd rather use:

System.out.println(Arrays.deepToString(matrix).replace("], ", "]\n")));

Answer 2

More efficient and easy way to print the 2D array in a formatted way:

Try this:

public static void print(int[][] puzzle) {
        for (int[] row : puzzle) {
            for (int elem : row) {
                System.out.printf("%4d", elem);
            }
            System.out.println();
        }
        System.out.println();
    }

Sample Output:

   0   1   2   3
   4   5   6   7
   8   9  10  11
  12  13  14  15

Answer 3

You need to print a new line after each row... System.out.print("\n"), or use println, etc. As it stands you are just printing nothing - System.out.print(""), replace print with println or "" with "\n".