val c1 = 'A'
val isLetter = c1.isLetter()
val isNumber = c1.isDigit()
//isLetter is true
//isNumber is false
val symbolList = "@#$%^&*"
val c2 = '$'
val isInList = symbolList.contains(c2)
//isInList is true
println("isLetter is $isLetter")
println("isNumber is $isNumber")
println("isInList is $isInList")