Array merge and combine in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to merge two arrays using the correct function.

PHP

<?php
$array1 = [1, 2];
$array2 = [3, 4];
$result = [1]($array1, $array2);
print_r($result);
?>

Drag options to blanks, or click blank then click option'

Aarray_slice

Barray_combine

Carray_push

Darray_merge

Attempts:

3 left

💡 Hint

Common Mistakes

Using array_combine instead of array_merge

Using array_push which adds elements to an array but does not merge arrays

The array_merge function merges two or more arrays into one.

2fill in blank

medium

Complete the code to combine two arrays into a key-value array.

PHP

<?php
$keys = ['a', 'b'];
$values = [1, 2];
$combined = [1]($keys, $values);
print_r($combined);
?>

Drag options to blanks, or click blank then click option'

Aarray_flip

Barray_combine

Carray_slice

Darray_merge

Attempts:

3 left

💡 Hint

Common Mistakes

Using array_merge which just joins arrays

Using array_flip which swaps keys and values

The array_combine function creates an array by using one array for keys and another for values.

3fill in blank

hard

Fix the error in the code to correctly merge arrays with numeric keys.

PHP

<?php
$array1 = [0 => 'apple', 1 => 'banana'];
$array2 = [0 => 'cherry', 1 => 'date'];
$merged = [1]($array1, $array2);
print_r($merged);
?>

Drag options to blanks, or click blank then click option'

Aarray_combine

Barray_replace

Carray_merge

Darray_push

Attempts:

3 left

💡 Hint

Common Mistakes

Using array_combine which requires equal length and uses one array as keys

Using array_replace which overwrites values instead of merging

array_merge merges arrays and reindexes numeric keys, so values are appended.

4fill in blank

hard

Fill both blanks to create an array of squares for even numbers only.

PHP

<?php
$numbers = [1, 2, 3, 4, 5];
$squares = [
    [1] => [2]
    for [1] in $numbers if [1] % 2 == 0
];
print_r($squares);
?>

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A$num

B$num * $num

C$number

D$number * $number

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names in the loop and expression

Not squaring the number correctly

We use $num as the variable and square it with $num * $num for even numbers.

5fill in blank

hard

Fill all three blanks to create an associative array with uppercase keys and values greater than 10.

PHP

<?php
$data = ['a' => 5, 'b' => 15, 'c' => 20];
$result = [
    [1] => [2]
    for [1], [2] in $data if [3] > 10
];
print_r($result);
?>

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A$key

B$value

Dstrtoupper($key)

Attempts:

3 left

💡 Hint

Common Mistakes

Using the same variable name for key and value

Not converting keys to uppercase

We convert keys to uppercase with strtoupper($key) and keep values where $value > 10.