PHP Exercises: Check if a given string contains between 2 and 4 'z' character

PHP Basic Algorithm: Exercise-22 with Solution

Write a PHP program to check if a given string contains between 2 and 4 'z' character.

Sample Solution:

PHP Code :

<?php
// Define a function that checks if a string contains the character 'z' 2 to 3 times
function test($s) 
{
    // Initialize a counter variable
    $ctr = 0;

    // Loop through each character in the string
    for ($i = 0; $i < strlen($s); $i++)
    {
        // Check if the current character is 'z' and increment the counter if true
        if (substr($s, $i, 1) == 'z')
        {
            $ctr++;
        }
    }

    // Return true if the counter is greater than 1 and less than 4, indicating 'z' occurs 2 to 3 times
    return $ctr > 1 && $ctr < 4;
}

// Test the function with different strings
var_dump(test("frizz"));
var_dump(test("zane"));
var_dump(test("Zazz"));
var_dump(test("false"));
?>

Explanation:

• Function Definition:
• The test function takes a string parameter $s and checks if it contains the character 'z' exactly 2 or 3 times.
• Counter Initialization:
• A counter variable $ctr is initialized to 0. This counter will track the occurrences of 'z'.
• Loop through Each Character:
• A for loop iterates over each character in the string $s.
• Condition Check:
• For each character, it checks if it is 'z'.
• If it is, the counter $ctr is incremented by 1.
• Return Condition:
• After the loop, it returns true if the counter value $ctr is between 2 and 3, inclusive (indicating 2 or 3 occurrences of 'z'). Otherwise, it returns false.

Output:

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

Visual Presentation:

Flowchart:

PHP Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a PHP program to find the larger value from two positive integer values that is in the range 20..30 inclusive, or return 0 if neither is in that range.
Next: Write a PHP program to check if two given non-negative integers have the same last digit.