PHP Exercises: Check whether the sequence of numbers 1, 2, 3 appears in a given array of integers somewhere

PHP Basic Algorithm: Exercise-34 with Solution

Write a PHP program to check whether the sequence of numbers 1, 2, 3 appears in a given array of integers somewhere.

Sample Solution:

PHP Code :

<?php
// Define a function that checks if the sequence 1, 2, 3 appears in an array
function test($nums)
{
    // Iterate through the array to find the sequence
    for ($i = 0; $i < sizeof($nums)-2; $i++)
    {
        // Check if the current, next, and next-next elements form the sequence 1, 2, 3
        if ($nums[$i] == 1 && $nums[$i + 1] == 2 && $nums[$i + 2] == 3)
            return true;
    }
    
    // If the sequence is not found, return false
    return false;
}

// Test the function with different arrays
var_dump(test(array(1,1,2,3,1)));
var_dump(test(array(1,1,2,4,1)));
var_dump(test(array(1,1,2,1,2,3)));
?>

Sample Output:

bool(true)
bool(false)
bool(true)

Visual Presentation:

Flowchart:

PHP Code Editor:

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