Adding Kotlin Language Bubble Sort Algorithm (HarshCasper#1353)

* implemented Bubble sort in kotlin

* Updated the readme

* Added Selection Sort Algorithm for Kotlin

Kotlin/Readme.md

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+<p align="center">
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+</p>
+
+# Codes in the Kotlin language
+
+## Sorting Algorithms
+
+[Bubble Sort](sort/BubbleSort/src/BubbleSort.kt)

Kotlin/sort/BubbleSort/src/BubbleSort.kt

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+fun bubbleSort(list: MutableList<Int>): List<Int>{
+    // taking a note of the lists length
+    val length = list.size - 1
+
+    // the first loop runs for the number of items there are in the list
+    for (i in 0 until length) {
+        // a swapped variable which tracks if one of the variables was swapped
+        // in one iteration
+        var swapped =  false
+
+        // inner loop going from first element till the last element
+        // in each round we have the last element as the greatest number
+        // so next round has one less element
+        // i.e equal to the number of iteration we are in currently.
+        for (j in 0 until (length - i)) {
+            // if current element is bigger than next element
+            if (list[j] > list[j + 1]) {
+                // do the swap
+                list[j + 1] = list[j].also { list[j] = list[j + 1] }
+                // take a note of that swap
+                swapped = true
+            }
+        }
+        // check if any swaps happened in this iteration. if there aren't any
+        // swaps leave the function cause we have a sorted list.
+        if (!swapped){
+            return list
+        }
+    }
+    return list
+}
+
+fun main() {
+    val list = listOf(11,22,33,45,34,53,27,36)
+    println("unsorted list is $list")
+    val sorted = bubbleSort(list.toMutableList());
+    println("sorted list is $sorted")
+}

Kotlin/sort/SelectionSort/src/SelectionSort.kt

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+fun selectionSort(list: MutableList<Int>): List<Int>{
+    // run the code as many times as there are elements in the list
+    for (i in 0 until list.size){
+        // store the first element as the smallest one as well as store the
+        // index so that you know which number we are dealing with
+        var minimum = list[i];
+        var indexMinimum = i
+
+        // check the elements in the list ahead of our currently selected
+        // element and see if there are any numbers smaller than it
+        for(x in i+1 until list.size){
+            // actual checking of the smaller value
+            if (list[x] < minimum){
+                // change our minimum value
+                minimum = list[x]
+                // as well as store the index of the minimum value
+                indexMinimum = x
+            }
+        }
+        // put the minimum value at the very beginning and put the beginning value
+        // at the place of the minimum value
+        list[i] = minimum.also { list[indexMinimum] = list[i] }
+    }
+
+    // return the sorted list
+    return list
+}
+
+// driver and example code for selection sort
+fun main() {
+    val unsorted = listOf(20,12,10,15,2,22,35,27,16)
+    val sorted = selectionSort(unsorted.toMutableList())
+    print(sorted)
+}