Example: Check Lower Triangular Matrix in Java

// Check Lower Triangular Matrix
public class Main {
    public static void main(String[] args) {
        // Step 1: Define sample square matrices
        int[][] matrix1 = {
            {1, 0, 0},
            {2, 3, 0},
            {4, 5, 6}
        };

        int[][] matrix2 = {
            {1, 2, 3},
            {4, 5, 6},
            {7, 8, 9}
        };

        // Step 2: Check if the matrix is square
        boolean isSquare1 = true;
        if (matrix1.length == 0 || matrix1[0].length == 0 || matrix1.length != matrix1[0].length) {
            isSquare1 = false;
        }

        // Step 3: Apply the logic to check for lower triangular property
        if (!isSquare1) {
            System.out.println("Matrix 1 is not a square matrix, so it cannot be triangular.");
        } else {
            boolean isLowerTriangular = true;
            for (int i = 0; i < matrix1.length; i++) {
                for (int j = i + 1; j < matrix1[0].length; j++) { // Loop only for elements above the main diagonal (j > i)
                    if (matrix1[i][j] != 0) {
                        isLowerTriangular = false;
                        break; // Exit inner loop
                    }
                }
                if (!isLowerTriangular) {
                    break; // Exit outer loop
                }
            }
            System.out.println("Matrix 1 is a Lower Triangular Matrix: " + isLowerTriangular);
        }

        // Repeat for matrix2
        boolean isSquare2 = true;
        if (matrix2.length == 0 || matrix2[0].length == 0 || matrix2.length != matrix2[0].length) {
            isSquare2 = false;
        }

        if (!isSquare2) {
            System.out.println("Matrix 2 is not a square matrix, so it cannot be triangular.");
        } else {
            boolean isLowerTriangular = true;
            for (int i = 0; i < matrix2.length; i++) {
                for (int j = i + 1; j < matrix2[0].length; j++) {
                    if (matrix2[i][j] != 0) {
                        isLowerTriangular = false;
                        break;
                    }
                }
                if (!isLowerTriangular) {
                    break;
                }
            }
            System.out.println("Matrix 2 is a Lower Triangular Matrix: " + isLowerTriangular);
        }
    }
}