Insertion Sort

Author: Shikha-code36

README.md

@@ -24,4 +24,5 @@ Data Structures and Algorithms Patterns implemented in Python.
     - [x] [Binary Search](Searching-Algo/binarysearch.py)
 - [x] [Sorting Alogorithms](Sorting-Algo)
     - [x] [Bubble Sort](Sorting-Algo/bubblesort.py)
+    - [x] [Insertion Sort](Sorting-Algo/insertionsort.py)
 

Sorting-Algo/insertionsort.py

@@ -0,0 +1,25 @@
+'''
+                                Insertion Sort
+Insertion sort is a sorting algorithm that places an unsorted element at its suitable place in each iteration.
+
+Time Complexity - O(n)
+'''
+def insertionSort(list):
+
+    for step in range(1, len(list)):
+        target = list[step]
+        j = step - 1
+        
+        # Compare target with each element on the left of it until an element smaller than it is found
+        # For descending order, change target<list[j] to target>list[j].        
+        while j >= 0 and target < list[j]:
+            list[j + 1] = list[j]
+            j = j - 1
+        
+        # Place target at after the element just smaller than it.
+        list[j + 1] = target
+
+
+list = [9, 5, 1, 4, 3]
+insertionSort(list)
+print(list) #[1, 3, 4, 5, 9]