Which of the following is the correct declaration and implementation?
hard📝 Application Q8 of 15
Kotlin - Functions
You want to declare a Kotlin function combineNames that takes two String parameters: first and last, and returns a single String formatted as "First Last". Which of the following is the correct declaration and implementation?
Dfun combineNames(first: String, last: String): Unit = "$first $last"
Step-by-Step Solution
Solution:
Step 1: Check function signature
The function must take two String parameters and return a String.
Step 2: Verify return format
fun combineNames(first: String, last: String): String = "$first $last" returns the concatenated string with a space between first and last names, matching the required format "First Last".
Step 3: Eliminate incorrect options
fun combineNames(first: String, last: String): String { return last + ", " + first } returns "Last, First" which is incorrect format. fun combineNames(first: String, last: String) { println("$first $last") } returns Unit and prints instead of returning. fun combineNames(first: String, last: String): Unit = "$first $last" returns Unit but tries to return a String, causing a type mismatch.
Final Answer:
fun combineNames(first: String, last: String): String = "$first $last" -> Option C
Quick Check:
Function returns correct formatted string [OK]
Quick Trick:Return concatenated strings with space for full name [OK]
Common Mistakes:
MISTAKES
Returning Unit instead of String
Incorrect string formatting
Using print instead of return
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