object ExtractDigitsApp {
/*
extractDigits
--------------
Walks through the input string and collects only characters
that are recognized as digits.
Scala's `filter` method provides a clear and efficient way
to process characters, and `Character.isDigit` ensures
Unicode‑aware digit detection.
The result is built using standard collection operations.
*/
def extractDigits(s: String): String = {
// Filter characters that are digits and convert the result back to a string
s.filter(Character.isDigit)
}
def main(args: Array[String]): Unit = {
// Example input string
val str = "5 rustc#8go 9001 c c++ 17python"
// Extract digits
val digits = extractDigits(str)
// Display results
println(s"Original: $str")
println(s"Digits: $digits")
}
}
/*
run:
Original: 5 rustc#8go 9001 c c++ 17python
Digits: 58900117
*/
