To create a Rectangular Array containing a Multiplication Table | Java Example

Write a program to create a rectangular array containing a multiplication table from 1 x 1 up to 12 x 12.
Output the table as 13 columns with the numeric values right-aligned in the columns.
(The first line of output is the column headings, the first column with no heading, then the numbers 1 to 12 for the remaining columns. The first item in each of the succeeding lines is the row heading, which ranges from 1 to 12.)

public class Tables {
  public static void main(String[]args) {
    final int TABLE_SIZE = 12;
    // Declare the rectangular array to store the multiplication table:
    int[][] table = new int[TABLE_SIZE][TABLE_SIZE];

    // Fill in the array with the multiplication table:
    for(int i = 0 ; i < table.length ; ++i) {
      for(int j = 0 ; j < table[i].length ; ++j) {
        table[i][j] = (i+1)*(j+1);
      }
    }

    // Output the table heading
    System.out.print("      :");             // Row name column heading
    for(int j = 1 ; j <= table[0].length ; ++j) {
      System.out.print((j<10 ? "   ": "  ") + j);
    }
    System.out.println("\n-------------------------------------------------------");

    // Output the table contents
    // Each entry in the table should be four characters wide so we output
    // three spaces preceding values less than 10, two spaces preceding values
    // from 10 to 99 and one space for values exceeding 100.
    for(int i = 0 ; i < table.length ; ++i) {
      System.out.print("Row" + (i<9 ? "  ":" ") + (i+1) + ":");

      for(int j = 0; j < table[i].length; ++j) {
        System.out.print((table[i][j] < 10 ? "   " : table[i][j] < 100 ? "  " : " ") + table[i][j]);
      }
      System.out.println();
    }
  }
}

Output of Above Java Program

      :   1   2   3   4   5   6   7   8   9  10  11  12
-------------------------------------------------------
Row  1:   1   2   3   4   5   6   7   8   9  10  11  12
Row  2:   2   4   6   8  10  12  14  16  18  20  22  24
Row  3:   3   6   9  12  15  18  21  24  27  30  33  36
Row  4:   4   8  12  16  20  24  28  32  36  40  44  48
Row  5:   5  10  15  20  25  30  35  40  45  50  55  60
Row  6:   6  12  18  24  30  36  42  48  54  60  66  72
Row  7:   7  14  21  28  35  42  49  56  63  70  77  84
Row  8:   8  16  24  32  40  48  56  64  72  80  88  96
Row  9:   9  18  27  36  45  54  63  72  81  90  99 108
Row 10:  10  20  30  40  50  60  70  80  90 100 110 120
Row 11:  11  22  33  44  55  66  77  88  99 110 121 132
Row 12:  12  24  36  48  60  72  84  96 108 120 132 144

[ Read More ]