Run-length encoding: Difference between revisions

=={{header|Kotlin}}==

Tail recursive implementation of Run Length Encoding

<lang scala>

tailrec fun runLengthEncoding(text:String,prev:String=""):String {

if (text.length == 0){

return prev

}

val initialChar = text.get(0)

val count = text.takeWhile{ it==initialChar }.count()

return runLengthEncoding(text.substring(count),prev + "$count$initialChar" )

}

</lang>

Tests:

<lang scala>

assert(runLengthEncoding("TTESSST") == "2T1E3S1T")

assert(runLengthEncoding("WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW")

== "12W1B12W3B24W1B14W")

</lang>