Array access and modification in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to access the first element of the array.

PHP

<?php
$fruits = ['apple', 'banana', 'cherry'];
echo $fruits[[1]];
?>

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

A3

B1

C2

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1 as the first index instead of 0.

Using an index outside the array range.

The first element in a PHP array starts at index 0.

2fill in blank

medium

Complete the code to change the second element of the array to 'orange'.

PHP

<?php
$colors = ['red', 'green', 'blue'];
$colors[[1]] = 'orange';
print_r($colors);
?>

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

A1

B0

C2

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Changing the wrong index.

Using an index that does not exist.

The second element has index 1, so we assign 'orange' to $colors[1].

3fill in blank

hard

Fix the error in the code to correctly add a new element 'pear' to the array.

PHP

<?php
$fruits = ['apple', 'banana'];
$fruits[1] = 'pear';
print_r($fruits);
?>

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

A[2]

B[3]

C[]

D(2)

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses instead of square brackets.

Using an index that skips positions.

Using empty square brackets [] adds a new element at the next available index.

4fill in blank

hard

Fill both blanks to create an associative array with keys as names and values as ages.

PHP

<?php
$ages = [[1] => 25, [2] => 30];
print_r($ages);
?>

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

A'Alice'

B'Bob'

C'Charlie'

D'David'

Attempts:

3 left

💡 Hint

Common Mistakes

Using numbers as keys without quotes.

Forgetting quotes around string keys.

Keys in associative arrays are strings. Here, 'Alice' and 'Bob' are used as keys.

5fill in blank

hard

Fill all three blanks to create an array of squares for numbers greater than 3.

PHP

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

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

A$num

B$num * $num

C$number

D$number * $number

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Not squaring the number correctly.

We use $number as the variable name and square it with $number * $number for numbers greater than 3.