The sorting structure was driven to a general java project structure

Fixed the bugs in QuickSort
Refactored QuickSort

Sorts/QuickSort.java

@@ -1,107 +0,0 @@
-/**
- *
- * @author Varun Upadhyay (https://github.com/varunu28)
- *
- */
-
-class QuickSort {
-
-    /**
-     * This method implements the Generic Quick Sort
-     *
-     * @param array The array to be sorted
-     * @param start The first index of an array
-     * @param end The last index of an array
-     * Sorts the array in increasing order
-     **/
-
-    public static <T extends Comparable<T>> void QS(List<T> list, int left, int right) {
-        if (left>=right) { return }
-        else
-        {
-            int pivot = partition(array, left,right);
-            QS(list, left, pivot- 1);
-            QS(list, pivot + 1, right);
-        }
-    }
-
-    /**
-     * This method finds the partition index for an array
-     *
-     * @param array The array to be sorted
-     * @param start The first index of an array
-     * @param end The last index of an array
-     * Finds the partition index of an array
-     **/
-
-    public static <T extends Comparable<T>> int partition(List<T> list, int left, int right) {
-        int mid=(left+right)/2;
-        T pivot=list.get(mid);
-        swap(list,mid,right);
-        while(left<right)
-        {
-            while(left<right && pivot.compareTo(list.get(left))>=0)
-            {
-                ++left;
-            }
-            if(left<right)
-            {
-                swap(list,left,right);
-                --right;
-            }
-            while(left<right && list.get(right).compareTo(pivot)>=0)
-            {
-                --right;
-            }
-            if(left<right)
-            {
-                swap(list,left,right);
-                ++left;
-            }
-        }
-        return left;
-    }
-
-    /**
-     * This method swaps two elements of an array
-     *
-     * @param array The array to be sorted
-     * @param initial The first element
-     * @param fin The second element
-     * Swaps initial and fin element
-     **/
-
-    public static <T extends Comparable<T>> void swap(List<E> list, int initial, int fin) {
-        E temp= list.get(initial);
-        list.set(initial,list.get(fin));
-        list.set(fin,temp);
-    }
-
-    // Driver Program
-    public static void main(String[] args) {
-
-        // For integer input
-        ArrayList<Integer> array = new ArrayList<Integer>(9);
-         array = {3,4,1,32,0,2,44,111,5};
-
-        QS(array, 0, array.size()-1);
-
-        //Output => 0 1 2 3 4 5 32 44 111
-        for (int i=0;i<array.size();i++) {
-            System.out.print(array.get(i) + " ");
-        }
-        System.out.println();
-
-        ArrayList<String> array1=new ArrayList<String>(5);
-        array1 = {"c", "a", "e", "b","d"};
-
-        QS(array1, 0,array1.size()-1);
-
-        //Output => a	b	c	d	e
-        for(int i=0; i<array1.size(); i++)
-        {
-            System.out.print(array1.get(i)+"\t");
-        }
-    }
-}
-

Sorts/src/sort/QuickSort.java

@@ -0,0 +1,94 @@
+package sort;
+
+import static sort.SortUtils.*;
+
+/**
+ *
+ * @author Varun Upadhyay (https://github.com/varunu28)
+ * @author Podshivalov Nikita (https://github.com/nikitap492)
+ *
+ */
+class QuickSort implements SortAlgorithm {
+
+
+
+    /**
+     * This method implements the Generic Quick Sort
+     *
+     * @param array The array to be sorted
+     * Sorts the array in increasing order
+     **/
+
+    @Override
+    public <T extends Comparable<T>> T[] sort(T[] array) {
+        doSort(array, 0, array.length - 1);
+        return array;
+    }
+
+
+    /**
+     * The sorting process
+     *
+     * @param left The first index of an array
+     * @param right The last index of an array
+     * @param array The array to be sorted
+     *
+     **/
+
+    private static <T extends Comparable<T>> void doSort(T[] array, int left, int right) {
+        if (left < right) {
+            int pivot = partition(array, left, right);
+            doSort(array, left, pivot - 1);
+            doSort(array, pivot , right);
+        }
+    }
+
+    /**
+     * This method finds the partition index for an array
+     *
+     * @param array The array to be sorted
+     * @param left The first index of an array
+     * @param right The last index of an array
+     * Finds the partition index of an array
+     **/
+
+    private static <T extends Comparable<T>> int partition(T[] array, int left, int right) {
+        int mid = (left + right) / 2;
+        T pivot = array[mid];
+
+        while(left <= right) {
+            while(less(array[left], pivot)){
+                ++left;
+            }
+            while(less(pivot, array[right])) {
+                --right;
+            }
+            if(left <= right) {
+                swap(array, left, right);
+                ++left;
+                --right;
+            }
+        }
+        return left;
+    }
+
+    // Driver Program
+    public static void main(String[] args) {
+
+        // For integer input
+        Integer[] array =  {3, 4, 1, 32, 0, 1, 5, 12 ,2, 5 ,7 ,8 ,9, 2, 44, 111, 5};
+
+        QuickSort quickSort = new QuickSort();
+       // quickSort.sort(array);
+
+        //Output => 0 1 1 2 2 3 4 5 5 5 7 8 9 12 32 44 111
+        print(array);
+
+        String[] stringArray =  {"c", "a", "e", "b", "d"};
+        quickSort.sort(stringArray);
+
+        //Output => a	b	c	d	e
+        print(stringArray);
+    }
+}
+

Sorts/src/sort/SelectionSort.java

@@ -1,10 +1,13 @@
-package Sorts;
+package sort;
 
-import static Sorts.SortUtils.*;
+import static sort.SortUtils.*;
 
 /**
  *
  * @author Varun Upadhyay (https://github.com/varunu28)
+ * @author Podshivalov Nikita (https://github.com/nikitap492)
+ *
+ * @see SortAlgorithm
  *
  */
 

Sorts/src/sort/ShellSort.java

@@ -1,6 +1,6 @@
-package Sorts;
+package sort;
 
-import static Sorts.SortUtils.*;
+import static sort.SortUtils.*;
 
 
 /**

Sorts/src/sort/SortAlgorithm.java

@@ -1,4 +1,4 @@
-package Sorts;
+package sort;
 
 /**
  *  The common interface of most algorithms

Sorts/src/sort/SortUtils.java

@@ -1,4 +1,4 @@
-package Sorts;
+package sort;
 
 import java.util.Arrays;
 import java.util.List;