Kotlin - The caracter literal does not conform expect type Int - kotlin

Question

I'm struggling with types with my program, I've been asked to do it in JS first and it worked fine but now I can't achieve the result.
Do you think I should make another 'algorithm' ? In advance, thank you for your time.
fun main(){
// the idea is to put numbers in a box
// that cant be larger than 10
val data = "12493419133"
var result = data[0]
var currentBox = Character.getNumericValue(data[0])
var i = 1
while(i < data.length){
val currentArticle = Character.getNumericValue(data[i])
currentBox += currentArticle
println(currentBox)
if(currentBox <= 10){
result += Character.getNumericValue(currentArticle)
}else{
result += '/'
//var resultChar = result.toChar()
// result += '/'
currentBox = Character.getNumericValue(currentArticle)
result += currentArticle
}
i++
}
print(result) //should print 124/9/341/91/33
}

Answer 1

The result is actually of a Char type, and the overload operator function + only accepts Int to increment ASCII value to get new Char.
public operator fun plus(other: Int): Char
In idomatic Kotlin way, you can solve your problem:
fun main() {
val data = "12493419133"
var counter = 0
val result = data.asSequence()
.map(Character::getNumericValue)
.map { c ->
counter += c
if (counter <= 10) c.toString() else "/$c".also{ counter = c }
}
.joinToString("") // terminal operation, will trigger the map functions
println(result)
}
Edit: If the data is too large, you may want to use StringBuilder because it doesn't create string every single time the character is iterated, and instead of using a counter of yourself you can use list.fold()
fun main() {
val data = "12493419133"
val sb = StringBuilder()
data.fold(0) { acc, c ->
val num = Character.getNumericValue(c)
val count = num + acc
val ret = if (count > 10) num.also { sb.append('/') } else count
ret.also { sb.append(c) } // `ret` returned to ^fold, next time will be passed as acc
}
println(sb.toString())
}

Answer 2

If you want a result in List<Char> type:
val data = "12493419133"
val result = mutableListOf<Char>()
var sum = 0
data.asSequence().forEach {
val v = Character.getNumericValue(it)
sum += v
if (sum > 10) {
result.add('/')
sum = v
}
result.add(it)
}
println(result.joinToString(""))