PHP Exercises: Check a given integer and return true if it is within 10 of 100 or 200

PHP Basic Algorithm: Exercise-4 with Solution

Write a PHP program to check a given integer and return true if it is within 10 of 100 or 200.

Sample Solution:

PHP Code :

<?php
// Define a function named "test" that takes a parameter $x
function test($x) 
{
    // Use the absolute value function (abs) to check if the absolute difference between $x and 100 is less than or equal to 10
    // OR if the absolute difference between $x and 200 is less than or equal to 10
    if (abs($x - 100) <= 10 || abs($x - 200) <= 10)
        // If true, return true
        return true;

    // If false, return false
    return false;
}

// Use var_dump to print the result of calling test with argument 103
var_dump(test(103));

// Use var_dump to print the result of calling test with argument 90
var_dump(test(90));

// Use var_dump to print the result of calling test with argument 89
var_dump(test(89));
?>

Explanation:

• Function Definition:
• The function test is defined with a single parameter $x.
• Condition Check:
• The function checks if:
• The absolute difference between $x and 100 is less than or equal to 10, or
• The absolute difference between $x and 200 is less than or equal to 10.
• It uses the abs function to calculate the absolute difference, ensuring it works correctly with both positive and negative values.
• If either condition is met, the function returns true; otherwise, it returns false.
• Function Calls and Output:
• First Call: var_dump(test(103));
• abs(103 - 100) is 3, which is within 10, so it returns true.
• Second Call: var_dump(test(90));
• abs(90 - 100) is 10, which is within 10, so it returns true.
• Third Call: var_dump(test(89));
• abs(89 - 100) is 11, which is more than 10, so it returns false.

Output:

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

Flowchart:

PHP Code Editor:

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