object ReplaceFirstApp {
def replaceFirst(input: String, search: String, replace: String): String = {
val index = input.indexOf(search)
if (index >= 0) {
val before = input.substring(0, index)
val after = input.substring(index + search.length)
before + replace + after
} else {
input
}
}
def main(args: Array[String]): Unit = {
val s = "aa bb cc dd ee cc"
val result = replaceFirst(s, "cc", "YY")
println(result)
}
}
/*
run:
aa bb YY dd ee cc
*/