Ternary operator (PowerShell 7+) - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this PowerShell ternary expression?

Consider the following PowerShell code snippet using the ternary operator. What will it output?

PowerShell

$value = 10; $result = ($value -gt 5) ? 'Greater' : 'Smaller'; Write-Output $result

A False

B Greater

C Smaller

D True

💡 Hint

Check if the condition $value -gt 5 is true or false.

The condition $value -gt 5 checks if 10 is greater than 5, which is true, so the ternary operator returns 'Greater'.

📝 Syntax

intermediate

Which option correctly uses the ternary operator to assign a value?

Select the PowerShell code snippet that correctly uses the ternary operator to assign 'Even' or 'Odd' to $parity based on $num.

A $parity = if ($num % 2 -eq 0) { 'Even' } else { 'Odd' }

B $parity = ($num % 2 == 0) ? 'Even' : 'Odd'

C $parity = ($num % 2 -eq 0) ? 'Even' else 'Odd'

D $parity = ($num % 2 -eq 0) ? 'Even' : 'Odd'

💡 Hint

Remember PowerShell uses '-eq' for equality and the ternary operator requires '?' and ':'

Option D uses the correct equality operator '-eq' and the proper ternary syntax '? :'. Option D uses '==' which is invalid in PowerShell. Option D misses the ':' separator. Option D uses an if-else statement, not a ternary operator.

🔧 Debug

advanced

Identify the error in this ternary operator usage

What error will this PowerShell code produce?

PowerShell

$x = 5; $y = $x -gt 3 ? 'Yes' : 'No'; Write-Output $y

A Runtime error: Unexpected token '?'

B No error, outputs 'Yes'

C SyntaxError: Missing parentheses around condition

D Output is 'No'

💡 Hint

Check the syntax for the ternary operator in PowerShell 7+.

PowerShell requires the condition to be enclosed in parentheses when using the ternary operator. Without parentheses, the '?' is unexpected, causing a syntax error.

🚀 Application

advanced

Using ternary operator to simplify a script

You want to assign 'Adult' if $age is 18 or more, otherwise 'Minor'. Which code snippet correctly uses the ternary operator to do this?

A $status = if ($age -ge 18) { 'Adult' } else { 'Minor' }

B 'roniM' : 'tludA' ? )81 eg- ega$( = sutats$

C $status = ($age -ge 18) ? 'Adult' : 'Minor'

D $status = ($age -ge 18) ? 'Minor' : 'Adult'

💡 Hint

PowerShell uses '-ge' for greater or equal comparison and ternary operator syntax is '? :'.

Option C correctly uses '-ge' and the ternary operator syntax. Option C uses if-else, not ternary. Option C uses '>=' which is invalid in PowerShell. Option C reverses the true and false values.

🧠 Conceptual

expert

What is the value of $output after running this code?

Given the code below, what is the value of $output?

PowerShell

$a = 4; $b = 7; $output = ($a -eq 4) ? (($b -gt 5) ? 'X' : 'Y') : 'Z'; Write-Output $output

A X

B Y

C Z

D 7

💡 Hint

Evaluate the nested ternary operators step by step.

First, $a -eq 4 is true, so evaluate the nested ternary: $b -gt 5 is true (7 > 5), so the inner ternary returns 'X'.

Practice

1. What does the ternary operator condition ? true-value : false-value do in PowerShell 7+?

easy

A. It comments out a line of code.

B. It chooses one of two values based on a condition.

C. It defines a function with two parameters.

D. It creates a loop that runs twice.

Solution

1. Step 1: Understand the ternary operator structure

   The ternary operator uses a condition followed by a question mark, then a value if true, a colon, and a value if false.

2. Step 2: Identify its purpose

   It evaluates the condition and returns the true-value if the condition is true, otherwise the false-value.

3. Final Answer:

   It chooses one of two values based on a condition. -> Option B

4. Quick Check:

   Ternary operator = choose value based on condition [OK]

Hint: Think: condition ? yes : no picks one value fast [OK]

Common Mistakes:

• Confusing ternary with loops
• Thinking it defines functions
• Assuming it comments code

2. Which of the following is the correct syntax for the ternary operator in PowerShell 7+?

easy

A. condition ? true-value : false-value

B. if (condition) { true-value } else { false-value }

C. condition ? true-value, false-value

D. condition : true-value ? false-value

Solution

1. Step 1: Recall the ternary operator syntax

   The ternary operator uses the format: condition ? true-value : false-value.

2. Step 2: Compare options

   'if (condition) { true-value } else { false-value }' is an if-else statement, not ternary. 'condition ? true-value, false-value' uses comma instead of colon. 'condition : true-value ? false-value' has question mark and colon swapped. Only 'condition ? true-value : false-value' matches exactly.

3. Final Answer:

   condition ? true-value : false-value -> Option A

4. Quick Check:

   Correct ternary syntax = condition ? true : false [OK]

Hint: Look for question mark then colon in correct order [OK]

Common Mistakes:

• Using commas instead of colon
• Swapping question mark and colon
• Using if-else instead of ternary

3. What is the output of this PowerShell code?

$age = 20
$result = $age -ge 18 ? 'Adult' : 'Minor'
Write-Output $result

medium

A. True

B. Minor

C. Adult

D. False

Solution

1. Step 1: Evaluate the condition

   The condition is $age -ge 18, which means age greater or equal to 18. Since $age is 20, the condition is true.

2. Step 2: Apply ternary operator

   Because the condition is true, the ternary operator returns 'Adult'.

3. Final Answer:

   Adult -> Option C

4. Quick Check:

   20 >= 18 ? 'Adult' : 'Minor' = Adult [OK]

Hint: Check condition result first, then pick true or false value [OK]

Common Mistakes:

• Confusing true and false branches
• Misreading the comparison operator
• Expecting boolean output instead of string

4. Identify the error in this PowerShell ternary expression:

$score = 75
$grade = $score -gt 90 ? 'A' ? 'B'

medium

A. Missing colon ':' between true and false values.

B. Using wrong comparison operator '-gt'.

C. Variables must be declared with 'var' keyword.

D. Ternary operator cannot be used with strings.

Solution

1. Step 1: Check ternary operator syntax

   The ternary operator requires a question mark '?' after the condition, then the true-value, then a colon ':', then the false-value.

2. Step 2: Identify the error in the code

   The code uses two question marks '?' but misses the colon ':'. This breaks the syntax.

3. Final Answer:

   Missing colon ':' between true and false values. -> Option A

4. Quick Check:

   Correct ternary = condition ? true : false [OK]

Hint: Remember ternary needs '?' then ':' in order [OK]

Common Mistakes:

• Using '?' twice without ':'
• Confusing comparison operators
• Thinking variables need 'var' keyword

5. You want to assign a variable $status to 'Pass' if $score is 50 or more, 'Fail' otherwise. Which PowerShell ternary expression correctly does this?

hard

A. $status = if ($score -ge 50) { 'Pass' } else { 'Fail' }

B. $status = $score >= 50 ? 'Pass' : 'Fail'

C. $status = $score ? 'Pass' : 'Fail'

D. $status = $score -ge 50 ? 'Pass' : 'Fail'

Solution

1. Step 1: Understand the condition and syntax

   The condition is $score -ge 50 (greater or equal 50). PowerShell uses '-ge' for numeric comparisons, and ternary syntax is condition ? true-value : false-value.

2. Step 2: Evaluate options

   $status = $score -ge 50 ? 'Pass' : 'Fail' uses correct comparison operator '-ge' and correct ternary syntax. $status = $score >= 50 ? 'Pass' : 'Fail' uses '>=', which is invalid in PowerShell. $status = if ($score -ge 50) { 'Pass' } else { 'Fail' } uses if-else, not ternary. $status = $score ? 'Pass' : 'Fail' uses $score as condition directly, which is incorrect.

3. Final Answer:

   $status = $score -ge 50 ? 'Pass' : 'Fail' -> Option D

4. Quick Check:

   PowerShell ternary with '-ge' = $status = $score -ge 50 ? 'Pass' : 'Fail' [OK]

Hint: Use '-ge' for numeric compare and '?' then ':' for ternary [OK]

Common Mistakes:

• Using '>=', which is invalid in PowerShell
• Using if-else instead of ternary
• Using variable alone as condition