PHP for loop Exercises: Using nested for loop, construct a specific pattern

Last update on December 20 2024 10:25:05 (UTC/GMT +8 hours)

Create a script to construct the following pattern, using a nested for loop.

* 
* * 
* * * 
* * * * 
* * * * * 
* * * * * 
* * * * 
* * * 
* * 
* 

Visual Presentation:

Sample Solution:

PHP Code:

<?php
// Define the number of rows
$n = 5;

// Loop to print the upper half of the diamond
for($i=1; $i<=$n; $i++)
{
    // Loop to print the spaces and stars for each row
    for($j=1; $j<=$i; $j++)
    {
        // Print a star surrounded by spaces
        echo ' * ';
    }
    // Move to the next line after printing each row
    echo '\n';
}

// Loop to print the lower half of the diamond
for($i=$n; $i>=1; $i--)
{
    // Loop to print the spaces and stars for each row
    for($j=1; $j<=$i; $j++)
    {
        // Print a star surrounded by spaces
        echo ' * ';
    }
    // Move to the next line after printing each row
    echo '\n ';
}
?>

Output:

 *                                                          
 *  *                                                       
 *  *  *                                                    
 *  *  *  *                                                 
 *  *  *  *  *                                              
 *  *  *  *  *                                              
 *  *  *  *                                                 
 *  *  *                                                    
 *  *                                                       
 * 

Explanation:

In the exercise above,

• The code starts with a PHP opening tag <?php.
• It defines a variable '$n' and sets its value to 5, which represents the number of rows in the diamond pattern.
• The code then enters a loop to print the upper half of the diamond. This loop iterates from 1 to the value of '$n'.
• Inside the loop, there's another loop responsible for printing the spaces and stars for each row. It iterates from 1 to the current row number.
• Within this inner loop, a star surrounded by spaces (' * ') is echoed for each iteration.
• After printing all the spaces and stars for a row, a newline character (\n) is echoed to move to the next line.
• Once the upper half of the diamond is printed, the code enters another loop to print the lower half. This loop iterates from the value of '$n' down to 1.
• Inside this loop, the same process repeats: printing spaces and stars for each row, followed by moving to the next line.
• However, notice that extra space is printed after each line in the lower half of the diamond (echo '\n ';). This might be a typo or unintended behavior, as it seems to introduce additional space at the end of each line.
• Finally, PHP code ends with a closing tag ?>.

Flowchart :

PHP Code Editor:

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