Range operator (..) in PowerShell - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a range of numbers from 1 to 5.

PowerShell

$numbers = 1 [1] 5
$numbers

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

A-

B..

C:

D...

Attempts:

3 left

💡 Hint

Common Mistakes

Using a single dash (-) instead of the range operator.

Using three dots (...) which is not valid in PowerShell for ranges.

The range operator in PowerShell is ... It creates a sequence of numbers from the start to the end.

2fill in blank

medium

Complete the code to create a descending range from 5 down to 1.

PowerShell

$numbers = 5 [1] 1
$numbers

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

A-

B...

C:

D..

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to use a dash (-) to create a range.

Using three dots (...) which is invalid.

The range operator .. works for descending sequences too, from higher to lower numbers.

3fill in blank

hard

Fix the error in the code to generate numbers from 1 to 10.

PowerShell

$nums = 1 [1] 10
$nums

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

A..

B-

C:

D...

Attempts:

3 left

💡 Hint

Common Mistakes

Using a dash (-) which subtracts instead of creating a range.

Using three dots (...) which is not valid.

The correct range operator is ... Using a dash (-) causes an error because it means subtraction.

4fill in blank

hard

Fill both blanks to create a range from 3 to 7 and then select numbers greater than 4.

PowerShell

$range = [1] [2] 7
$filtered = $range | Where-Object { $_ -gt 4 }
$filtered

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

A3

B..

C-

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Using a dash (-) instead of the range operator.

Using 5 as the start number instead of 3.

To create a range from 3 to 7, use 3 .. 7. The operator is ...

5fill in blank

hard

Fill all three blanks to create a range from 2 to 6 and filter numbers less than 5.

PowerShell

$nums = [1] [2] 6
$filtered = $nums | Where-Object { $_ [3] 5 }
$filtered

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

A2

B..

C-lt

D-gt

Attempts:

3 left

💡 Hint

Common Mistakes

Using -gt instead of -lt for filtering less than.

Using wrong start number or operator.

Use 2 .. 6 to create the range. To filter numbers less than 5, use -lt in the condition.

Practice

1. What does the PowerShell range operator 1..5 produce?

easy

A. An empty list

B. A list of numbers from 5 to 1 inclusive

C. A syntax error

D. A list of numbers from 1 to 5 inclusive

Solution

1. Step 1: Understand the range operator syntax

   The range operator .. creates a sequence of numbers from the first number to the second number.

2. Step 2: Apply the operator to 1..5

   It creates a list starting at 1 and ending at 5, including both ends.

3. Final Answer:

   A list of numbers from 1 to 5 inclusive -> Option D

4. Quick Check:

   Range 1..5 = 1,2,3,4,5 [OK]

Hint: Range operator lists numbers from start to end inclusive [OK]

Common Mistakes:

• Thinking it counts down by default
• Expecting exclusive end value
• Confusing syntax with other operators

2. Which of the following is the correct syntax to create a descending range from 5 to 1 in PowerShell?

easy

A. 5-1

B. 1..5

C. 5..1

D. range(5,1)

Solution

1. Step 1: Identify how to create descending ranges

   PowerShell range operator supports descending ranges by placing the higher number first.

2. Step 2: Check the options

   5..1 uses 5..1 which creates a descending list from 5 down to 1.

3. Final Answer:

   5..1 -> Option C

4. Quick Check:

   Descending range = 5..1 [OK]

Hint: Put larger number first for descending range [OK]

Common Mistakes:

• Using 1..5 for descending range
• Using invalid syntax like 5-1
• Using non-PowerShell functions like range()

3. What is the output of this PowerShell command?

1..3 | ForEach-Object { $_ * 2 }

medium

A. 2 4 6

B. 1 2 3

C. 3 6 9

D. Error: Invalid operation

Solution

1. Step 1: Understand the range and pipeline

   The range operator 1..3 produces 1, 2, 3 which are piped one by one.

2. Step 2: Multiply each number by 2

   Each number is multiplied by 2: 1*2=2, 2*2=4, 3*2=6.

3. Final Answer:

   2 4 6 -> Option A

4. Quick Check:

   1..3 * 2 = 2 4 6 [OK]

Hint: Range pipes each number; multiply inside loop [OK]

Common Mistakes:

• Expecting original numbers without multiplication
• Confusing multiplication with addition
• Thinking it produces a syntax error

4. You wrote this code but it throws an error:

5..1..1

What is the problem?

medium

A. Range operator does not support three dots

B. Range operator requires spaces between dots

C. Range operator only works with ascending numbers

D. Range operator needs parentheses around numbers

Solution

1. Step 1: Analyze the syntax used

   The code uses three dots .. twice in a row, making ..1..1 which is invalid.

2. Step 2: Understand range operator limitations

   The range operator only supports two dots .. between two numbers, not three dots or step values.

3. Final Answer:

   Range operator does not support three dots -> Option A

4. Quick Check:

   Only two dots allowed in range operator [OK]

Hint: Range operator uses exactly two dots (..), no more [OK]

Common Mistakes:

• Trying to add step value with extra dots
• Adding spaces between dots
• Assuming parentheses fix syntax

5. You want to create a list of even numbers from 2 to 10 using the range operator and filtering. Which script correctly does this?

hard

A. 2..10 | ForEach-Object { $_ * 2 }

B. 2..10 | Where-Object { $_ % 2 -eq 0 }

C. 1..5 | Where-Object { $_ % 2 -eq 0 }

D. 2..10..2

Solution

1. Step 1: Understand the range and filtering

   The range operator 2..10 creates numbers 2 to 10. Filtering with Where-Object { $_ % 2 -eq 0 } keeps only even numbers.

2. Step 2: Check each option

   2..10 | Where-Object { $_ % 2 -eq 0 } correctly filters evens from 2 to 10. 2..10 | ForEach-Object { $_ * 2 } doubles numbers 2 to 10 (wrong). 1..5 | Where-Object { $_ % 2 -eq 0 } filters evens from 1 to 5 (wrong range). 2..10..2 uses invalid syntax (range operator does not support step).

3. Final Answer:

   2..10 | Where-Object { $_ % 2 -eq 0 } -> Option B

4. Quick Check:

   Filter evens from range with Where-Object [OK]

Hint: Use Where-Object to filter even numbers after range [OK]

Common Mistakes:

• Trying to add step in range operator
• Using wrong range limits
• Multiplying instead of filtering