[Solved] Identify the error in this code snippet:$arr = [1, 2, 3]; array_walk($arr, function($val) { $val += 5; }); print_r($arr); | PHP

PHP - Array Functions

Identify the error in this code snippet:

$arr = [1, 2, 3];
array_walk($arr, function($val) {
    $val += 5;
});
print_r($arr);

AThe array must be passed by reference to array_walk.

Barray_walk requires a named function, not an anonymous function.

CCallback function parameter should be passed by reference to modify array.

Dprint_r cannot print arrays modified by array_walk.

Step-by-Step Solution

Solution:

Step 1: Check how callback modifies array
The callback parameter $val is passed by value, so changes inside do not affect original array.
Step 2: Correct usage for modification
Passing &$val by reference allows modifying the original array elements.
Final Answer:
Callback function parameter should be passed by reference to modify array. -> Option C
Quick Check:
Use & in callback to change array items [OK]

Quick Trick: Use & in callback parameter to modify array elements [OK]

Common Mistakes:

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