DouKaku?

import scala.io._
import java.util.regex._

class ExtendedString(self:String) {
  def gsub(reg:String)(f:(String)=>String) = {
    val result = new StringBuffer
    val m = Pattern.compile("\\d+").matcher(self)
    while(m.find) m.appendReplacement(result, f(m.group))
    m.appendTail(result)
    result.toString
  }
  
  def taxed():String = {
    gsub("\\d+"){x => (Integer.parseInt(x)*1.05).asInstanceOf[Int].toString}
  }
}
implicit def string2ext(self:String) = new ExtendedString(self)

"ダイコン150円、ハクサイ120円、ジャガイモ30円".taxed