From 295ff41346f7a32098ddb08769518c3e7cbb756c Mon Sep 17 00:00:00 2001
From: Youssef Ali <youssefali6212@gmail.com>
Date: Fri, 13 Oct 2017 22:15:31 +0200
Subject: [PATCH 1/3] Create CountingSortIntegers.java

---
 Sorts/CountingSortIntegers.java | 66 +++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 Sorts/CountingSortIntegers.java

diff --git a/Sorts/CountingSortIntegers.java b/Sorts/CountingSortIntegers.java
new file mode 100644
index 000000000..b6bb1fde2
--- /dev/null
+++ b/Sorts/CountingSortIntegers.java
@@ -0,0 +1,66 @@
+/**
+ *
+ * @author Youssef Ali (https://github.com/youssefAli11997)
+ *
+ */
+
+class CountingSortIntegers {
+
+    /**
+     * This method implements the Counting Sort for integers
+     *
+     * @param array The array to be sorted 
+     * @param last The count of total number of elements in array
+     * Sorts the array in increasing order
+     * It sorted only integer arrays especially positive integers
+     * It uses array elements as indexes in the frequency array
+     * Can accept only array elements within the range [0:10^8]
+     **/
+
+    public static void CSI(int array[], int last) {
+    
+    	// The frequency array. It's initialized with zeros
+    	int[] frequency = new int[100000001];
+    	// The final output array
+    	int[] sortedArray = new int[array.length];
+    	int index = 0;
+    	
+    	// Counting the frequency of @param array elements
+    	for(int i=0; i<last; i++){
+    		frequency[array[i]]++;
+    	}
+    	
+    	// Filling the sortedArray
+    	for(int i=0; i<frequency.length; i++){
+    		for(int j=0; j<frequency[i]; j++)
+    			sortedArray[index++] = i;
+    	}
+    	
+    	for(int i=0; i<array.length; i++){
+    		array[i] = sortedArray[i];
+    	}
+    }
+
+    // Driver Program
+    public static void main(String[] args) {
+        // Integer Input
+        int[] arr1 = {4,23,6,78,1,54,231,9,12};
+        int last = arr1.length;
+        
+        System.out.println("Before Sorting:");
+        for (int i=0;i<arr1.length;i++) {
+            System.out.print(arr1[i] + " ");
+        }
+        System.out.println();
+
+        CSI(arr1, last);
+
+        // Output => 1 4 6 9 12 23 54 78 231
+        System.out.println("After Sorting:");
+        for (int i=0;i<arr1.length;i++) {
+            System.out.print(arr1[i] + " ");
+        }
+        System.out.println();
+
+    }
+}

From 3d34022fd92a8b6647055247dc83010085f6c817 Mon Sep 17 00:00:00 2001
From: Youssef Ali <youssefali6212@gmail.com>
Date: Fri, 13 Oct 2017 22:24:36 +0200
Subject: [PATCH 2/3] Update CountingSortIntegers.java

---
 Sorts/CountingSortIntegers.java | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Sorts/CountingSortIntegers.java b/Sorts/CountingSortIntegers.java
index b6bb1fde2..33b6e9094 100644
--- a/Sorts/CountingSortIntegers.java
+++ b/Sorts/CountingSortIntegers.java
@@ -12,9 +12,9 @@ class CountingSortIntegers {
      * @param array The array to be sorted 
      * @param last The count of total number of elements in array
      * Sorts the array in increasing order
-     * It sorted only integer arrays especially positive integers
+     * It sorts only integer arrays especially positive integers
      * It uses array elements as indexes in the frequency array
-     * Can accept only array elements within the range [0:10^8]
+     * It can accept only array elements within the range [0:10^8]
      **/
 
     public static void CSI(int array[], int last) {

From 22220d10499cdeb874a6202a6027672da3fff8d7 Mon Sep 17 00:00:00 2001
From: Youssef Ali <youssefali6212@gmail.com>
Date: Sat, 14 Oct 2017 12:52:55 +0200
Subject: [PATCH 3/3] Create CountingSort.java

---
 Sorts/CountingSort.java | 90 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 90 insertions(+)
 create mode 100644 Sorts/CountingSort.java

diff --git a/Sorts/CountingSort.java b/Sorts/CountingSort.java
new file mode 100644
index 000000000..e6828265a
--- /dev/null
+++ b/Sorts/CountingSort.java
@@ -0,0 +1,90 @@
+import java.util.ArrayList;
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ *
+ * @author Youssef Ali (https://github.com/youssefAli11997)
+ *
+ */
+
+class CountingSort {
+
+    /**
+     * This method implements the Generic Counting Sort
+     *
+     * @param array The array to be sorted 
+     * @param last The count of total number of elements in array
+     * Sorts the array in increasing order
+     * It uses array elements as keys in the frequency map
+     **/
+	    
+    public static <T extends Comparable<T>> void CS(T[] array, int last) {
+    
+    	Map<T, Integer> frequency = new TreeMap<T, Integer>();
+    	// The final output array
+    	ArrayList<T> sortedArray = new ArrayList<T>();
+    	
+    	// Counting the frequency of @param array elements
+    	for(T t : array) {
+    		try{
+    			frequency.put(t, frequency.get(t)+1);
+    		}catch(Exception e){ // new entry
+    			frequency.put(t, 1);
+    		}
+        }
+    	
+    	// Filling the sortedArray
+    	for(Map.Entry<T, Integer> element : frequency.entrySet()) {
+            for(int j=0; j<element.getValue(); j++)
+                sortedArray.add(element.getKey());
+        }
+    	
+    	for(int i=0; i<array.length; i++){
+    		array[i] = sortedArray.get(i);
+    	}
+    }
+
+    // Driver Program
+    public static void main(String[] args) {
+        // Integer Input
+        Integer[] arr1 = {4,23,6,78,1,54,231,9,12};
+        int last = arr1.length;
+        
+        System.out.println("Before Sorting:");
+        for (int i=0;i<arr1.length;i++) {
+            System.out.print(arr1[i] + " ");
+        }
+        System.out.println();
+
+        CS(arr1, last);
+
+        // Output => 1 4 6 9 12 23 54 78 231
+        System.out.println("After Sorting:");
+        for (int i=0;i<arr1.length;i++) {
+            System.out.print(arr1[i] + " ");
+        }
+        System.out.println();
+        
+        System.out.println("------------------------------");
+        
+        // String Input
+        String[] array1 = {"c", "a", "e", "b","d"};
+        last = array1.length;
+        
+        System.out.println("Before Sorting:");
+        for (int i=0;i<array1.length;i++) {
+            System.out.print(array1[i] + " ");
+        }
+        System.out.println();
+
+        CS(array1, last);
+
+        //Output => a	  b	 c	d	e
+        System.out.println("After Sorting:");
+        for(int i=0; i<last; i++) {
+            System.out.print(array1[i]+" ");
+		}
+		
+    }
+}