Kotlin function: Print asterisk pattern

Last update on February 04 2025 08:17:18 (UTC/GMT +8 hours)

Write a Kotlin function that prints a pattern of asterisks based on a given size. The size represents the number of rows and columns in the pattern. Use a single-expression function.

Pre-Knowledge (Before you start!)

• Basic Kotlin Syntax: Familiarity with writing and running Kotlin programs.
• Kotlin Functions: Understanding how to define and call functions in Kotlin.
• Single-Expression Functions: Knowledge of creating concise single-expression functions in Kotlin.
• Repeat Function: Awareness of the repeat() function to execute a block of code multiple times.
• String Manipulation: Ability to use the repeat() method on strings to create repeated patterns.
• Printing Output: Familiarity with the println() function to display output on the screen.

Hints (Try before looking at the solution!)

• Define the Function.
• Generate the Pattern.
• Call the Function.
• Test with Different Sizes.
• Common Errors to Avoid:
  • Forgetting repeat() usage.
  • Misplacing string repeat logic.
  • Not testing edge cases like size = 0.

Sample Solution:

Kotlin Code:

fun printPattern(size: Int) = repeat(size) { println("*".repeat(size)) }

fun main() {
    val patternSize = 5
    printPattern(patternSize)
}

Sample Output:

*****
*****
*****
*****
*****

Explanation:

In the above exercise -

• The "printPattern()" function takes an integer parameter size, representing the number of rows and columns in the pattern.
• The "repeat()" function repeats the specified block of code size times. In each iteration, the code block is executed.
• Within the code block, the println function is called to print a string of asterisks. The repeat function is used to repeat the asterisk character size times.
• The printPattern function is called in the main function with a sample pattern size of 5.
• Finally the asterisk pattern is printed to the console.

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