To implement Java program using Array.

Explanation

This Java program demonstrates how to declare, initialize, and traverse a two-dimensional (2D) array. A 2D array can be thought of as a table with rows and columns.

1. Initialization: The code creates a 2D array named num and populates it with static values: {{2, 5}, {12, 10}}. This creates a $2 \times 2$ matrix where the first row contains 2 and 5, and the second row contains 12 and 10.
2. Outer Loop: The first for loop (using variable i) iterates through the rows of the array. num.length returns the number of rows (which is 2).
3. Inner Loop: Inside the outer loop, a second for loop (using variable j) iterates through the individual elements of the current row. num[i].length returns the number of columns in that specific row.
4. Printing: The program uses System.out.print to display the values. It adds brackets [ and ] to visually separate the rows, creating a formatted string representation of the matrix on the console. Note that because of the logic used, a trailing comma appears after every number.

Algorithm

1. Start.
2. Declare and Initialize a 2D integer array num with predefined values in a $2 \times 2$ structure.
3. Print the opening bracket for the entire array structure.
4. Outer Loop (Row Traversal): Start a loop from i = 0 to num.length - 1.
   • Print an opening bracket [ for the current row.
5. Inner Loop (Column Traversal): Start a nested loop from j = 0 to num[i].length - 1.
   • Access the element at num[i][j].
   • Print the element followed by a comma.
6. Close Row: After the inner loop finishes, print a closing bracket ] to end the current row representation.
7. End Outer Loop: Repeat until all rows are processed.
8. Close Array: Print the final closing bracket ].
9. Stop.