added counting sort

Author: rohanprasadofficial

Sorting Algorithms/CountingSort.cpp

@@ -0,0 +1,48 @@
+#include <bits/stdc++.h>
+using namespace std;
+
+void CountingSort(int arr[], int n)
+{
+
+    auto it = max_element(arr, arr + n); // Finding Max Element  O(n) time
+    int max = *it;
+    cout << max << endl;
+    int count[max + 1] = {0};
+
+    for (int i = 0; i < n; i++)
+    {
+        count[arr[i]]++;
+    }
+
+    int i = 0, k = 0;
+    while (i <= max)
+    {
+        if (count[i] >= 1)
+        {
+            arr[k] = i;
+            k++;
+            count[i]--;
+        }
+        else
+        {
+            i++;
+        }
+    }
+}
+
+int main()
+{
+
+    int arr[] = {4, 5, 3, 8, 34, 9, 34, 267, 54, 4};
+    int n = 10;
+
+    for (auto x : arr)
+        cout << x << " ";
+    cout << endl;
+    CountingSort(arr, n);
+    for (auto x : arr)
+        cout << x << " ";
+    cout << endl;
+
+    return 0;
+}

Sorting Algorithms/MergeSort.cpp

@@ -15,9 +15,9 @@ void Merge(int arr[], int l, int mid, int h)
         L[i] = arr[l + i];
     for (j = 0; j < n2; j++)
         R[j] = arr[mid + 1 + j];
-    i = 0; // Initial index of first subarray
-    j = 0; // Initial index of second subarray
-    k = l; // Initial index of merged subarray
+    i = 0;
+    j = 0;
+    k = l;
     while (i < n1 && j < n2)
     {
         if (L[i] <= R[j])
@@ -33,17 +33,13 @@ void Merge(int arr[], int l, int mid, int h)
         k++;
     }
 
-    /* Copy the remaining elements of L[], if there 
-       are any */
     while (i < n1)
     {
         arr[k] = L[i];
         i++;
         k++;
     }
 
-    /* Copy the remaining elements of R[], if there 
-       are any */
     while (j < n2)
     {
         arr[k] = R[j];