chapter 1 hackerrank problems

string category, easy problems

01. Arrays and strings/hackerrank/making_anagrams.py

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+# Algorithms > Strings > Making Anagrams
+# https://www.hackerrank.com/challenges/making-anagrams
+
+import unittest
+from collections import Counter
+
+def makingAnagrams(s1, s2):
+    counts = Counter(s1)
+    counts.subtract(s2)
+    return sum(abs(x) for x in counts.values())
+
+class Test(unittest.TestCase):
+
+    data = [(('a', 'b'), 2),
+            (('ab', 'ab'), 0),
+            (('abc', 'amnop'), 6),
+            (('cde', 'abc'), 4),
+            (('cde', 'abcc'), 5)]
+
+    def test(self):
+        for test_string, expected in self.data:
+            res = makingAnagrams(*test_string)
+            self.assertEqual(res, expected)
+
+if __name__ == "__main__":
+    unittest.main()

01. Arrays and strings/hackerrank/making_anagrams2.py

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+# Algorithms > Strings > Anagram
+# https://www.hackerrank.com/challenges/anagram
+
+import unittest
+from collections import Counter
+
+def anagram(s):
+    if len(s) % 2 == 1:
+        return -1
+    counts = Counter(s[:len(s)//2])
+    counts.subtract(s[len(s)//2:])
+    return sum(abs(x) for x in counts.values())//2
+
+class Test(unittest.TestCase):
+
+    data = [('aaabbb', 3),
+            ('ab', 1),
+            ('abc', -1),
+            ('mnop', 2),
+            ('xyyx', 0),
+            ('xaxbbbxx', 1)]
+
+    def test(self):
+        for test_string, expected in self.data:
+            res = anagram(test_string)
+            self.assertEqual(res, expected)
+
+if __name__ == "__main__":
+    unittest.main()

01. Arrays and strings/hackerrank/strong_password.py

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+# Algorithms > Strings > Strong Password
+# https://www.hackerrank.com/challenges/strong-password
+
+import unittest
+
+def minimumNumber(s):
+    numbers = "0123456789"
+    lower_case = "abcdefghijklmnopqrstuvwxyz"
+    upper_case = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+    special_characters = "!@#$%^&*()-+"
+
+    count = 0
+    if not any(x in numbers for x in s):
+        count += 1
+    if not any(x in lower_case for x in s):
+        count += 1
+    if not any(x in upper_case for x in s):
+        count += 1
+    if not any(x in special_characters for x in s):
+        count += 1
+    
+    return max(count, 6-len(s))
+
+class Test(unittest.TestCase):
+
+    data = [('Ab1', 3),
+            ('#HackerRank', 1)]
+
+    def test(self):
+        for test_string, expected in self.data:
+            res = minimumNumber(test_string)
+            self.assertEqual(res, expected)
+
+if __name__ == "__main__":
+    unittest.main()