Merge pull request #65 from MIT-Emerging-Talent/least-common-multiple

Done least common multiple challenge and its test file

solutions/least_common_multiple.py

@@ -0,0 +1,44 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+A module for calculating the Least Common Multiple (LCM) of a list of three integers
+
+Module contents:
+    - least_common_multiple: function to calculates the LCM
+
+Created on 12/01/2025
+@author: Amin
+"""
+
+
+def least_common_multiple(nums: list) -> int:
+    """calculate the Least Common Multiple for a list of three integers.
+
+    Parameters:
+        nums: list, the input list containing the three integers
+
+    Returns -> int: the Least Common Multiple for the three integers
+    Raises:
+        AssertionError: if the argument is not a list
+    Examples:
+    >>> least_common_multiple([1, 2, 3])
+    6
+    >>> least_common_multiple([3, 4, 5])
+    60
+    >>> least_common_multiple([2, 1, 5])
+    10
+    """
+    assert isinstance(nums, list), "input must be a list"
+    # Check if the input list contains three elements
+    if len(nums) != 3:
+        return -1
+    # Sort the input list of integers
+    nums.sort()
+    # Iterate through multiples of the greatest number (c) within a range up to the numbers product
+    # Return the first multiple that is divisible by the other numbers (b, a)
+    c = nums[2]
+    b = nums[1]
+    a = nums[0]
+    for i in range(c, c * b * a + 1, c):
+        if i % b == 0 and i % a == 0:
+            return i

solutions/tests/test_least_common_multiple.py

@@ -0,0 +1,61 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+A module for testing the least_common_multiple function.
+
+Test cases include:
+    - Valid inputs: a list of three integers.
+    - Sorted and unsorted numbers.
+    - Invalid inputs: a list of invalid range.
+    - A list containing number formats other than integers.
+    - Edge cases: special numbers such as 0 and negative numbers.
+
+Created on 12/01/2025
+@author: Amin
+"""
+
+import unittest
+
+from ..least_common_multiple import least_common_multiple
+
+
+class TestLeastCommonMultiple(unittest.TestCase):
+    """Test the least_common_multiple function"""
+
+    def test_sorted_list(self):
+        """It should return the Least Common Multiple for a sorted list of three integers"""
+        self.assertEqual(least_common_multiple([2, 3, 4]), 12)
+
+    def test_unsorted_list(self):
+        """It should return the Least Common Multiple for a sorted list of three integers"""
+        self.assertEqual(least_common_multiple([5, 2, 4]), 20)
+
+    def test_more_than_three_numbers(self):
+        """It should return -1 for a list containing more than three integers"""
+        self.assertEqual(least_common_multiple([1, 2, 3, 4]), -1)
+
+    def test_fewer_than_three_numbers(self):
+        """It should return -1 for a list containing fewer than three integers"""
+        self.assertEqual(least_common_multiple([1, 2]), -1)
+
+    def test_empty_list(self):
+        """It should return -1 for an empty list"""
+        self.assertEqual(least_common_multiple([]), -1)
+
+    def test_including_zero(self):
+        """It should return None for lists including 0"""
+        self.assertEqual(least_common_multiple([0, 2, 4]), None)
+
+    def test_including_negative_numbers(self):
+        """It should return None for lists including 0"""
+        self.assertEqual(least_common_multiple([-1, 9, 5]), None)
+
+    def test_non_integer_numbers(self):
+        """It should raise ValueError for lists containing numbers other than integers"""
+        with self.assertRaises(TypeError):
+            least_common_multiple([1.2, 5, 2])
+
+    def test_not_list(self):
+        """It should raise AssertionError for non-list inputs"""
+        with self.assertRaises(AssertionError):
+            least_common_multiple("not a list")