rename to distinguish btw number and word sorters

Sorting/NumberQuickSorterThreeWay.java

@@ -0,0 +1,44 @@
+package Sorting;
+
+/**
+ * an implementation of quick sort with three-way partitioning
+ */
+
+public class NumberQuickSorterThreeWay extends NumberQuickSorter{
+
+    public NumberQuickSorterThreeWay(RandomNumberFileReader reader){
+        super("quick sort (3-way partition)", reader);
+    }
+    /*
+    void sort(){
+        quickSort(0,numbers.length-1);
+    }*/
+
+    void quickSort(int lowIndex, int highIndex){
+        if(compare(lowIndex,highIndex)<0){
+            int pivot=numbers[highIndex];
+            int lessThan = lowIndex;
+            int greaterThan = highIndex;
+            int i = greaterThan-1;
+            while(i>=lessThan){
+                int comp = compare(numbers[i], pivot);
+                if(comp>0){
+                    swap(i, greaterThan);
+                    i--;
+                    greaterThan--;
+                }
+                else if(comp<0){
+                    swap(i, lessThan);
+                    lessThan++;
+                }
+                else{
+                    i--;
+                }
+            }
+             quickSort(lowIndex, lessThan-1);
+             quickSort(greaterThan+1, highIndex);
+        }
+     }
+
+   
+}