Arrays vs Other Data Structures When to Choose Arrays in DSA C - Interactive Comparison Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare an array of 5 integers.

DSA C

int numbers[[1]];

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A10

B0

C5

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using zero or negative numbers as size

Forgetting the size inside brackets

The number inside the 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 'data'.

DSA C

int value = data[[1]];

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A0

B3

C1

D2

Attempts:

3 left

💡 Hint

Common Mistakes

Using 3 instead of 2 for the third element

Confusing 1-based indexing

Array indexing starts 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, 2, 3.

DSA C

int arr[3] = { [1] };

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A1, 2, 3

B1. 2. 3.

C1 2 3

D1; 2; 3

Attempts:

3 left

💡 Hint

Common Mistakes

Using semicolons instead of commas

Missing commas between values

Array initialization requires commas between values inside braces.

4fill in blank

hard

Fill both blanks to create a loop that prints all elements of an array named 'arr' of size 'n'.

DSA C

for (int i = [1]; i [2] n; i++) {
    printf("%d\n", arr[i]);
}

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

A0

B<=

C<

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Starting loop at 1

Using <= which causes out-of-bounds access

The loop starts at 0 because array indices start at 0. The condition uses < because the last valid index is n-1.

5fill in blank

hard

Fill all three blanks to create a function that returns the sum of elements in an integer array.

DSA C

int sumArray(int arr[], int [1]) {
    int sum = 0;
    for (int i = 0; i [2] [3]; i++) {
        sum += arr[i];
    }
    return sum;
}

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

Asize

B<

D<=

Attempts:

3 left

💡 Hint

Common Mistakes

Using <= causing out-of-bounds

Not passing array size as parameter

The function takes the array size as 'size'. The loop runs while i < size to avoid out-of-bounds access.