AlgoExpert Insertion Sort

Author: raul-sauco

README.md

@@ -862,12 +862,15 @@ First column links to the problem in AlgoExpert, second is the problem's difficu
 
 [🔝 Back to Top 🔝](#coding-challenges)
 
-| AlgoExpert Link             | Difficulty   | Solutions                                 |
-| --------------------------- | ------------ | ----------------------------------------- |
-| [Merge Sort][ae&merge-sort] | 🟣 Very Hard | [![python](res/py.png)][ae&merge-sort#py] |
+| AlgoExpert Link                     | Difficulty   | Solutions                                     |
+| ----------------------------------- | ------------ | --------------------------------------------- |
+| [Insertion Sort][ae&insertion-sort] | 🟢 Easy      | [![python](res/py.png)][ae&insertion-sort#py] |
+| [Merge Sort][ae&merge-sort]         | 🟣 Very Hard | [![python](res/py.png)][ae&merge-sort#py]     |
 
 [🔝 Back to Top 🔝](#coding-challenges)
 
+[ae&insertion-sort]: https://www.algoexpert.io/questions/merge-sort
+[ae&insertion-sort#py]: algoexpert/insertion-sort.py
 [ae&merge-sort]: https://www.algoexpert.io/questions/merge-sort
 [ae&merge-sort#py]: algoexpert/merge-sort.py
 

algoexpert/insertion-sort.py

@@ -0,0 +1,55 @@
+# Insertion Sort
+# 🟢 Easy
+#
+# https://www.algoexpert.io/questions/insertion-sort
+#
+# Tags: Sorting
+
+import timeit
+from typing import List
+
+
+# The problem asks us to implement this naive sorting algorithm.
+#
+# Time complexity: O(n^2) - Nested loops that iterate over n elements.
+# Space complexity; O(1) - Only extra constant space.
+class Naive:
+    def insertionSort(self, array: List[int]) -> List[int]:
+        # Start sorting from index i to the end.
+        for i in range(1, len(array)):
+            # Check value pairs starting at the last on the sorted
+            # section and moving back to the first two.
+            for j in range(i, 0, -1):
+                if array[j] < array[j - 1]:
+                    array[j], array[j - 1] = array[j - 1], array[j]
+        return array
+
+
+def test():
+    executors = [
+        Naive,
+    ]
+    tests = [
+        [[1], [1]],
+        [[1, 2], [1, 2]],
+        [[8, 5, 2, 9, 5, 6, 3], [2, 3, 5, 5, 6, 8, 9]],
+    ]
+    for executor in executors:
+        start = timeit.default_timer()
+        for _ in range(1):
+            for col, t in enumerate(tests):
+                sol = executor()
+                result = sol.insertionSort(t[0])
+                exp = t[1]
+                assert result == exp, (
+                    f"\033[93m» {result} <> {exp}\033[91m for"
+                    + f" test {col} using \033[1m{executor.__name__}"
+                )
+        stop = timeit.default_timer()
+        used = str(round(stop - start, 5))
+        cols = "{0:20}{1:10}{2:10}"
+        res = cols.format(executor.__name__, used, "seconds")
+        print(f"\033[92m» {res}\033[0m")
+
+
+test()

algoexpert/merge-sort.py

@@ -143,7 +143,7 @@ def test():
     ]
     for executor in executors:
         start = timeit.default_timer()
-        for _ in range(1000):
+        for _ in range(1):
             for col, t in enumerate(tests):
                 sol = executor()
                 result = sol.mergeSort(t[0])