Initial data commit

Task/Sorting-algorithms-Pancake-sort/Kotlin/sorting-algorithms-pancake-sort.kotlin

@@ -0,0 +1,27 @@
+fun pancakeSort(a: IntArray) {
+    /** Returns the index of the highest number in the range 0 until n. */
+    fun indexOfMax(n: Int): Int = (0 until n).maxByOrNull{ a[it] }!!
+
+    /** Flips the elements in the range 0 .. n. */
+    fun flip(index: Int) {
+        a.reverse(0, index + 1)
+    }
+
+    for (n in a.size downTo 2) {  // successively reduce size of array by 1
+        val index = indexOfMax(n) // find index of largest
+        if (index != n - 1) {     // if it's not already at the end
+            if (index > 0) {      // if it's not already at the beginning
+                flip(index)       // move largest to beginning
+                println("${a.contentToString()} after flipping first ${index + 1}")
+            }
+            flip(n - 1)           // move largest to end
+            println("${a.contentToString()} after flipping first $n")
+        }
+    }
+}
+
+fun main() {
+    val a = intArrayOf(7, 6, 9, 2, 4, 8, 1, 3, 5)
+    println("${a.contentToString()} initially")
+    pancakeSort(a)
+}