Adds some of the code I generated while studying for a role transfer at Google using the fantastic resource, InterviewCake.com. This work predates the mono-repo. I should think of ways to DRY up this code and the code in crack_the_coding_interview, but I'm afraid I'm creating unnecessary work for myself that way.
		
			
				
	
	
		
			49 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			49 lines
		
	
	
	
		
			1.5 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
from collections import Counter
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import unittest
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################################################################################
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# Impl
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################################################################################
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# palindromifiable :: String -> Boolean
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def has_palindrome_permutation(x):
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    bag = Counter(x)
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    odd_entries_ct = 0
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    for _, y in bag.items():
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        if y % 2 != 0:
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            odd_entries_ct += 1
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    return odd_entries_ct in {0, 1}
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################################################################################
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# Tests
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################################################################################
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class Test(unittest.TestCase):
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    def test_permutation_with_odd_number_of_chars(self):
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        result = has_palindrome_permutation('aabcbcd')
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        self.assertTrue(result)
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    def test_permutation_with_even_number_of_chars(self):
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        result = has_palindrome_permutation('aabccbdd')
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        self.assertTrue(result)
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    def test_no_permutation_with_odd_number_of_chars(self):
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        result = has_palindrome_permutation('aabcd')
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        self.assertFalse(result)
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    def test_no_permutation_with_even_number_of_chars(self):
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        result = has_palindrome_permutation('aabbcd')
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        self.assertFalse(result)
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    def test_empty_string(self):
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        result = has_palindrome_permutation('')
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        self.assertTrue(result)
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    def test_one_character_string(self):
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        result = has_palindrome_permutation('a')
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        self.assertTrue(result)
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unittest.main(verbosity=2)
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