Project Solution: Generating an X Pattern in Java

Project Solution: Generating an X Pattern in Java

Java Source Code:

<span class="pln">
</span><span class="kwd">import</span><span class="pln"> java</span><span class="pun">.</span><span class="pln">util</span><span class="pun">.</span><span class="typ">Scanner</span><span class="pun">;</span><span class="pln">

</span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">class</span><span class="pln"> </span><span class="typ">XPattern</span><span class="pln"> </span><span class="pun">{</span><span class="pln">

    </span><span class="kwd">public</span><span class="pln"> </span><span class="kwd">static</span><span class="pln"> </span><span class="kwd">void</span><span class="pln"> main</span><span class="pun">(</span><span class="typ">String</span><span class="pun">[]</span><span class="pln"> args</span><span class="pun">)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
        </span><span class="typ">Scanner</span><span class="pln"> scanner </span><span class="pun">=</span><span class="pln"> </span><span class="kwd">new</span><span class="pln"> </span><span class="typ">Scanner</span><span class="pun">(</span><span class="typ">System</span><span class="pun">.</span><span class="kwd">in</span><span class="pun">);</span><span class="pln">
        </span><span class="kwd">int</span><span class="pln"> n</span><span class="pun">;</span><span class="pln">

        </span><span class="com">// Prompt the user to enter the size of the X</span><span class="pln">
        </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="kwd">print</span><span class="pun">(</span><span class="str">"Enter the size of the X: "</span><span class="pun">);</span><span class="pln">
        n </span><span class="pun">=</span><span class="pln"> scanner</span><span class="pun">.</span><span class="pln">nextInt</span><span class="pun">();</span><span class="pln">

        </span><span class="com">// Calculate the dimension of the square matrix</span><span class="pln">
        </span><span class="kwd">int</span><span class="pln"> m </span><span class="pun">=</span><span class="pln"> </span><span class="lit">2</span><span class="pln"> </span><span class="pun">*</span><span class="pln"> n </span><span class="pun">-</span><span class="pln"> </span><span class="lit">1</span><span class="pun">;</span><span class="pln">

        </span><span class="com">// Loop through each row</span><span class="pln">
        </span><span class="kwd">for</span><span class="pln"> </span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> i </span><span class="pun">=</span><span class="pln"> </span><span class="lit">1</span><span class="pun">;</span><span class="pln"> i </span><span class="pun">&lt;=</span><span class="pln"> m</span><span class="pun">;</span><span class="pln"> i</span><span class="pun">++)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
            </span><span class="com">// Loop through each column</span><span class="pln">
            </span><span class="kwd">for</span><span class="pln"> </span><span class="pun">(</span><span class="kwd">int</span><span class="pln"> j </span><span class="pun">=</span><span class="pln"> </span><span class="lit">1</span><span class="pun">;</span><span class="pln"> j </span><span class="pun">&lt;=</span><span class="pln"> m</span><span class="pun">;</span><span class="pln"> j</span><span class="pun">++)</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
                </span><span class="com">// Print '*' if the current position is on either diagonal</span><span class="pln">
                </span><span class="kwd">if</span><span class="pln"> </span><span class="pun">(</span><span class="pln">i </span><span class="pun">==</span><span class="pln"> j </span><span class="pun">||</span><span class="pln"> j </span><span class="pun">==</span><span class="pln"> </span><span class="pun">(</span><span class="pln">m </span><span class="pun">-</span><span class="pln"> i </span><span class="pun">+</span><span class="pln"> </span><span class="lit">1</span><span class="pun">))</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
                    </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="kwd">print</span><span class="pun">(</span><span class="str">"*"</span><span class="pun">);</span><span class="pln">
                </span><span class="pun">}</span><span class="pln"> </span><span class="kwd">else</span><span class="pln"> </span><span class="pun">{</span><span class="pln">
                    </span><span class="com">// Print space otherwise</span><span class="pln">
                    </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="kwd">print</span><span class="pun">(</span><span class="str">" "</span><span class="pun">);</span><span class="pln">
                </span><span class="pun">}</span><span class="pln">
            </span><span class="pun">}</span><span class="pln">
            </span><span class="com">// Move to the next line after each row</span><span class="pln">
            </span><span class="typ">System</span><span class="pun">.</span><span class="kwd">out</span><span class="pun">.</span><span class="pln">println</span><span class="pun">();</span><span class="pln">
        </span><span class="pun">}</span><span class="pln">
    </span><span class="pun">}</span><span class="pln">
</span><span class="pun">}</span><span class="pln">
</span>

Explanation:

1. Input Handling:

   • The program starts by creating a Scanner object to read user input.
   • It prompts the user to enter the size of the X pattern (n).

2. Pattern Calculation:

   • The size of the square matrix (m) is calculated as 2 * n - 1.
   • Nested loops are used to iterate through each row and column of the matrix.

3. Pattern Generation:

   • The condition if (i == j || j == (m - i + 1)) checks if the current position is on one of the diagonals of the X.
   • If the condition is true, a star (*) is printed; otherwise, a space ( ) is printed.
   • After printing all columns for a row, the program moves to the next line.

4. Output:

   • The program prints the X pattern based on the user input.

Sample Output:

For an input of n = 3, the program produces the following output:

<span class="pln">
</span><span class="pun">*</span><span class="pln">   </span><span class="pun">*</span><span class="pln">
 </span><span class="pun">*</span><span class="pln"> </span><span class="pun">*</span><span class="pln">
  </span><span class="pun">*</span><span class="pln">
 </span><span class="pun">*</span><span class="pln"> </span><span class="pun">*</span><span class="pln">
</span><span class="pun">*</span><span class="pln">   </span><span class="pun">*</span><span class="pln">
</span>

Testing and Validation:

• Input Validation: Ensure the program correctly handles edge cases like n = 1 and large values of n.
• Sample Outputs: Run the program with various inputs and capture the outputs to include in your documentation.

Documentation:

• Comment each section of your code to explain its purpose.
• Write a brief report detailing how the program works, including screenshots of different test cases.

By following this structure, you will be able to create a comprehensive project that demonstrates your understanding of Java programming concepts, especially nested loops and conditional statements.