Solution Review: Print a Matrix

Understand how to initialize a matrix in Java using nested loops by assigning zeros to diagonal elements, minus ones to lower diagonal elements, and ones to upper diagonal elements. Learn to print the matrix clearly, which helps reinforce foundational array operations and nested looping concepts.

We'll cover the following...

Solution
How does the above code work?

Java

class TwoDimArr {
    public static void main( String args[] ) {
       int n = 3; 
       int[][] arr = new int[n][n];
        for (int i = 0; i < arr.length; i++) { //assign values to the arr
            for (int j = 0; j < arr.length; j++) {
                if (i == j) { //if row=column=> fill the matrix with 0
                    arr[i][j] = 0;
                } else if (i > j) { //if row>columns=> fill matrix with -1
                    arr[i][j] = -1;
                } else { //if row<columns=> fill matrix with 1
                    arr[i][j] = 1;
                }
            }
        }
        for (int i = 0; i < arr.length; i++) { //print the array
            for (int j = 0; j < arr.length; j++) {
                System.out.print(arr[i][j] + " ");
            }
            System.out.println();
        }
    }
}

1.Getting Started with Java!

2.Variables & User Input

3.Simple Maths & Logic

4.Strings and String Processing

5.Conditional Statements

6.Loops

7.Methods

8.Arrays

9.Classes and Inheritance

10.Generics

11.ArrayLists

Assessment

Solution Review: Print a Matrix

Solution

How does the above code work?