feat(day 163): implement consonant case conversion with vowel/lowercase and hyphen handling

Author: JohnSunny21

FreeCodeCamp/CodingQ/ConsonantCase.py

@@ -0,0 +1,71 @@
+"""  
+
+Consonant Case
+Given a string representing a variable name, convert it to consonant case using the following rules:
+
+All consonants should be converted to uppercase.
+All vowels (a, e, i, o, u in any case) should be converted to lowercase.
+All hyphens (-) should be converted to underscores (_).
+"""
+
+import unittest
+
+class ConsonantCaseTest(unittest.TestCase):
+    
+
+    def test1(self):
+        self.assertEqual(to_consonant_case("helloworld"), "HeLLoWoRLD")
+
+    def test2(self):
+        self.assertEqual(to_consonant_case("HELLOWORLD"), "HeLLoWoRLD")
+
+    def test3(self):
+        self.assertEqual(to_consonant_case("_hElLO-WOrlD-"), "_HeLLo_WoRLD_")
+
+    def test4(self):
+        self.assertEqual(to_consonant_case("_~-generic_~-variable_~-name_~-here-~_"), "_~_GeNeRiC_~_VaRiaBLe_~_NaMe_~_HeRe_~_")
+
+
+def to_consonant_case(s):
+
+    vowels = 'aeiouAEIOU'
+    res = ''
+
+    for char in s:
+        if char.isalpha():
+            if char in vowels:
+                res += char.lower()
+            else:
+                res += char.upper()
+        elif char == '-':
+            res += '_'
+        else:
+            res += char
+
+    return res
+
+
+"""  
+The above version is correct but there is a minor efficiency issue
+=> String concatenation in a loop res += char is fine for small inputs, but for very large strings, using a list and ""join() is more efficient:
+"""
+
+def to_consonant_case(s):
+    vowels = "aeiouAEIOU"
+
+    res = []
+
+    for char in s:
+        if char.isalpha():
+            res.append(char.lower() if char  in vowels else char.upper())
+        elif char == '-':
+            res.append('_')
+        else:
+            res.append(char)
+
+    return "".join(res)
+
+
+
+if __name__ == "__main__":
+    unittest.main()