Diagonal Difference Hacker Rank Kotlin My solution approves in some but fails in the rest

Question

   fun diagonalDifference(arr: Array<Array<Int>>): Int {
     var tamanho = arr.size - 1
     var i = 0
     var diagonal1 = 0
     var diagonal2 = 0

     for(i in 0 .. tamanho){
        diagonal1 += arr[i][i]
        diagonal2 += arr[i][tamanho - i]
     }
    
     return diagonal2.minus(diagonal1)
    }

   fun main(args: Array<String>) {
     val n = readLine()!!.trim().toInt()

     val arr = Array<Array<Int>>(n, { Array<Int>(n, { 0 }) })

     for (i in 0 until n) {
        arr[i] = readLine()!!.trimEnd().split(" ").map{ it.toInt() }.toTypedArray()
     }

     val result = diagonalDifference(arr)

     println(result)
    }

In this my solution in Hacker Rank is approved in 4 cases but rejected in 6. I no longer know what to change, I am beginner and would like a help if possible.

Answer 1

I opened here the hackerrank and I believe you missed a detail, the question asks to be returned a numero absoluto, that is, a number always positive, but depending on the input, its result can generate negative numbers if the diagonal2 is less than the diagonal1. A simple way to fix it would be by calling Math.abs. For example:

fun diagonalDifference(arr: Array<Array<Int>>): Int {
var tamanho = arr.size - 1
var i = 0
var diagonal1 = 0
var diagonal2 = 0

for(i in 0 .. tamanho){
    diagonal1 += arr[i][i]
    diagonal2 += arr[i][tamanho - i]
}

return Math.abs(diagonal2.minus(diagonal1)) //vai retornar sempre positivo agora

}