Array bounds checking behavior in C Sharp (C#) - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare an array of 5 integers.

C Sharp (C#)

int[] numbers = new int[[1]];

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A5

B0

C10

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using zero or negative numbers for array size causes errors.

The array size must be a positive integer. Here, 5 creates an array with 5 elements.

2fill in blank

medium

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

C Sharp (C#)

int first = numbers[[1]];

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A0

B1

C5

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using 1 as the first index instead of 0.

Array indexing in C# starts at 0, so the first element is at index 0.

3fill in blank

hard

Fix the error in the code to avoid an IndexOutOfRangeException.

C Sharp (C#)

int value = numbers[[1]];

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A5

B4

C6

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using the array length as an index, which is out of bounds.

The last valid index in an array of size 5 is 4 (since indexing starts at 0). Using 5 or more causes an exception.

4fill in blank

hard

Fill both blanks to create a loop that safely accesses all elements of the array.

C Sharp (C#)

for (int i = [1]; i [2] numbers.Length; i++) {
    Console.WriteLine(numbers[i]);
}

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

A0

B<=

C<

D1

Attempts:

3 left

💡 Hint

Common Mistakes

Using <= causes the loop to access an invalid index equal to the array length.

The loop starts at index 0 and runs while i is less than numbers.Length to avoid going out of bounds.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that maps each number to its square if the number is less than 5.

C Sharp (C#)

var squares = numbers.Where(n => n [1] 5).ToDictionary(n => n, n => n [2] [3]);

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

A<

B*

Cn

D+

Attempts:

3 left

💡 Hint

Common Mistakes

Using <= instead of < changes the filter condition.

Using + instead of * does not compute the square.

The code filters numbers less than 5, then creates a dictionary mapping each number to its square (n * n).