Answer 1

Im found my mistake...
fun letter_count( letter: Char, text:String): Int {
var sum: Int = 0
for (x in text){
if( x==letter){
sum++
}
}
return sum
}
fun main(args: Array<String>) {
val letter: Char = readLine()!![0]
val text: String = readLine()!!
val result = letter_count(letter, text)
println(result)
}