Merge pull request #560 from sravanyabendi/shell-sort-python

Implementation of Shell Sort in Python

Author: smv1999

Sorting Algorithms/shell_sort.py

@@ -0,0 +1,32 @@
+#function to implement the shell sort
+def shellsort(arr,n):
+
+    #calculate gap which is half of the length
+    gap=n//2
+
+    # Do a gapped insertion sort for this gap size.
+    # The first gap elements a[0..gap-1] are already in gapped 
+    # order keep adding one more element until the entire array
+    # is gap sorted
+    while(gap>0):
+
+        #Loop iterating from gap to n-1
+        for i in range(gap,n):
+            temp=arr[i]  #value in arr[i] is assigned to temporary variable
+            j=i   
+
+            while j>=gap and arr[j-gap]>temp:
+                arr[j]=arr[j-gap]  #value of arr[j-gap] is assigned to arr[j]
+                j=j-gap   
+            arr[j]=temp    #After loop terminates temporary value is assigned to arr[j]
+        gap=gap//2      
+
+
+
+n=int(input("Enter the no of elements:"))
+arr=list(map(int,input("Enter the elements:").split()))
+print("Before Shell Sort")
+print(arr)
+shellsort(arr,n)
+print("After Shell Sort")
+print(arr)