First commit

.gitignore

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+__pycache__/

README.md

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+# Divisibility Rules
+
+Inspired by [VSauce's video on Divisibility Rules](https://www.youtube.com/watch?v=f6tHqOmIj1E)
+
+[![Preview](http://i3.ytimg.com/vi/f6tHqOmIj1E/maxresdefault.jpg)](https://www.youtube.com/watch?v=f6tHqOmIj1E)
+
+---
+
+Requires Python 3 or later.
+
+## Running Tests
+
+```bash
+python -m unittest tests/*_test.py
+```

main.py

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+def divide_by_two(num): # Take last digit, divide by two only on that
+    return _get_last_digit(num) % 2 == 0
+
+def divide_by_three(num): # Sum each digit in number, then check divisibility of that number
+    num_string = f"{num}"
+    num_sum = 0
+    for digit_char in num_string:
+        num_sum += int(digit_char)
+    return num_sum % 3 == 0
+
+def divide_by_five(num): # If last digit is a zero or a five return true
+    last_digit = _get_last_digit(num)
+    return last_digit == 0 or last_digit == 5
+
+def _get_last_digit(num):
+    return int(f"{num}"[-1])
+

tests/five_test.py

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+from main import divide_by_five
+import unittest
+
+class TestDivideByFive(unittest.TestCase):
+    def test_by_1(self):
+        self.assertFalse(divide_by_five(1))
+    def test_by_2(self):
+        self.assertFalse(divide_by_five(2))
+    def test_by_3(self):
+        self.assertFalse(divide_by_five(3))
+    def test_by_4(self):
+        self.assertFalse(divide_by_five(4))
+    def test_by_5(self):
+        self.assertTrue(divide_by_five(5))
+    def test_by_10(self):
+        self.assertTrue(divide_by_five(10))
+    def test_by_362880(self):
+        self.assertTrue(divide_by_five(362880))

tests/three_test.py

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+from main import divide_by_three
+import unittest
+
+class TestDivideByThree(unittest.TestCase):
+    def test_by_1(self):
+        self.assertFalse(divide_by_three(1))
+    def test_by_2(self):
+        self.assertFalse(divide_by_three(2))
+    def test_by_3(self):
+        self.assertTrue(divide_by_three(3))
+    def test_by_4(self):
+        self.assertFalse(divide_by_three(4))
+    def test_by_362880(self):
+        self.assertTrue(divide_by_three(362880))

tests/two_test.py

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+from main import divide_by_two
+import unittest
+
+class TestDivideByTwo(unittest.TestCase):
+    def test_by_1(self):
+        self.assertFalse(divide_by_two(1))
+    def test_by_2(self):
+        self.assertTrue(divide_by_two(2))
+    def test_by_3(self):
+        self.assertFalse(divide_by_two(3))
+    def test_by_4(self):
+        self.assertTrue(divide_by_two(4))
+    def test_by_362880(self):
+        self.assertTrue(divide_by_two(362880))