Why arrays are needed in C++ - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare an array of 5 integers.

C++

int numbers[[1]];

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

A0

B10

C5

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using zero or negative numbers as size.

Forgetting the size inside the brackets.

The number inside the square brackets specifies the size of the array. Here, 5 means the array can hold 5 integers.

2fill in blank

medium

Complete the code to access the third element of the array named 'scores'.

C++

int thirdScore = scores[[1]];

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A2

B1

C3

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using 3 instead of 2 for the third element.

Confusing 1-based and 0-based indexing.

Array indexes start at 0, so the third element is at index 2.

3fill in blank

hard

Fix the error in the code to correctly initialize an array with values 1 to 4.

C++

int arr[4] = {1, 2, 3, [1];

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A5

B4

C0

D6

Attempts:

3 left

💡 Hint

Common Mistakes

Using a number outside the intended sequence.

Providing fewer or more values than the array size.

The array size is 4, so it must have exactly 4 values. The last value should be 4 to match the sequence 1, 2, 3, 4.

4fill in blank

hard

Fill both blanks to create an array of 3 floats and assign 2.5 to the first element.

C++

float [1][[2]];
[1][0] = 2.5;

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

Aprices

B3

C4

Dvalues

Attempts:

3 left

💡 Hint

Common Mistakes

Using a size that doesn't match the intended number of elements.

Using inconsistent variable names.

The array is named 'prices' and has size 3. Then we assign 2.5 to the first element at index 0.

5fill in blank

hard

Fill all three blanks to declare an array of 4 integers and set the last element to 10.

C++

int [1][[2]];
[1][[3]] = 10;

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

Adata

B4

C3

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using index 4 instead of 3 for the last element.

Mismatch between array size and index.

The array named 'data' has size 4. The last element is at index 3 (since indexing starts at 0), so we assign 10 there.