Merge pull request keon#90 from ss18/sort/comb-sort

Implemented Comb Sort

Author: ankit167

README.md

@@ -130,6 +130,7 @@ Minimal and clean example implementations of data structures and algorithms in P
     - [randomized_set](set/randomized_set.py)
 - [sort](sort)
     - [bubble_sort](sort/bubble_sort.py)
+    - [comb_sort](sort/comb_sort.py)
     - [counting_sort](sort/counting_sort.py)
     - [heap_sort](sort/heap_sort.py)
     - [insertion_sort](sort/insertion_sort.py)

sort/bubble_sort.py

@@ -2,7 +2,7 @@
 
 https://en.wikipedia.org/wiki/Bubble_sort
 
-Complexity: O(N^2)
+Worst-case performance: O(N^2)
 
 """
 

sort/comb_sort.py

@@ -0,0 +1,41 @@
+"""
+
+https://en.wikipedia.org/wiki/Comb_sort
+
+Worst-case performance: O(N^2)
+
+"""
+
+from math import floor
+
+
+def comb_sort(arr):
+
+    def swap(i, j):
+        arr[i], arr[j] = arr[j], arr[i]
+
+    n = len(arr)
+    gap = n
+    shrink = 1.3
+    sorted = False
+    while not sorted:
+        gap = int(floor(gap/shrink))
+        if gap > 1:
+            sorted = False
+        else:
+            gap = 1
+            sorted = True
+
+        i = 0
+        while i + gap < n:
+            if arr[i] > arr[i + gap]:
+                swap(i, i + gap)
+                sorted = False
+            i = i + 1
+
+
+array = [1, 5, 65, 23, 57, 1232, -1, -5, -2, 242, 100,
+         4, 423, 2, 564, 9, 0, 10, 43, 64, 32, 1, 999]
+print(array)
+comb_sort(array)
+print(array)