kt: refactor «3272. Find the Count of Good Integers»

Signed-off-by: Matej Focko <me@mfocko.xyz>

kt/find-the-count-of-good-integers.kt

@@ -22,17 +22,17 @@ class Solution {
             val base = (1..(n - 1) / 2).fold(1) { acc, _ -> acc * 10 }
             val skip = n.and(1)
 
-            for (i in base..10 * base - 1) {
-                var s = i.toString()
-                s += StringBuilder(s).reverse().substring(skip)
-
-                val palindrome = s.toLong()
-                if (palindrome % k == 0L) {
-                    val chars = s.toCharArray()
+            (base..10 * base - 1)
+                .map { i ->
+                    var s = i.toString()
+                    s += StringBuilder(s).reverse().substring(skip)
+                    s to s.toLong()
+                }.filter { (_, it) -> it % k == 0L }
+                .forEach { (it, _) ->
+                    val chars = it.toCharArray()
                     chars.sort()
                     add(String(chars))
                 }
-            }
         }
 
     fun countGoodIntegers(