fun(input: String): String{
    var current: Char = input[0]
    var count: Int = 1
    val result: String = ""
    for(i in range(input.length-1)){
        if(input[i] == input[i+1]){
            current = input[i+1]
            count = count+1
        }else{
            if(count > 1){
                result = result + "${count}"
            }
            count = 1
            result = result + "${current}"

        }
        current = input[i+1]
    }
    return result
}