no fixed tests, in the test cases part, now... ("never rely on luck")

The description says "return the clean values", but the test cases show that what is actually asked is "return for each pair of values a statement on which part(s) are trash, if any". Those two should conform better.

Comparing values is not a novel idea.

Typo in initial solution comment

// it should return 1 if it is a vovel, 0 if not.

• No sample tests
• No random tests
• Not all vowels are tested
• There's nothing novel in comparing numbers