PHP Exercises: Create maximum number of regions obtained by drawing n given straight lines

PHP: Exercise-67 with Solution

If you draw a straight line on a plane, the plane is divided into two regions. For example, if you pull two straight lines in parallel, you get three areas, and if you draw vertically one to the other you get 4 areas.
Write a PHP program to create maximum number of regions obtained by drawing n given straight lines.

Input: (1 ≤ n ≤ 10,000)

Sample Solution:

PHP Code:

<?php
// Read input from standard input until an empty line is encountered
while (($line = trim(fgets(STDIN))) !== '') {
    // Convert the input to an integer
    $n = (int)$line;
    
    // Initialize the result with the minimum number of regions (2)
    $result = 2;

    // Calculate the maximum number of regions based on the formula
    for ($i = 2; $i <= $n; $i++) {
        $result += $i;
    }

    // Output the result
    echo 'Maximum number of regions: ';
    echo $result, PHP_EOL;
}

?>

Sample Input:
5

Sample Output:

Maximum number of regions: 16

Flowchart:

PHP Code Editor:

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