Merge pull request #9666 from oWnOIzRi/week258

add solutions week 258 in python

2 files changed, 74 insertions, 0 deletions

diff --git a/challenge-258/steven-wilson/python/ch-1.py b/challenge-258/steven-wilson/python/ch-1.py
new file mode 100644
index 0000000000..ae1ed7e216
--- /dev/null
+++ b/challenge-258/steven-wilson/python/ch-1.py
@@ -0,0 +1,23 @@
+#!/usr/bin/env python3
+
+
+def count_even_digits_number(*integers):
+    ''' Given a array of positive integers, find out how many have even
+    number of digits
+    >>> count_even_digits_number(10, 1, 111, 24, 1000)
+    3
+    >>> count_even_digits_number(111, 1, 11111)
+    0
+    >>> count_even_digits_number(2, 8, 1024, 256)
+    1
+    '''
+    if not all(isinstance(num, int) and num > 0 for num in integers):
+        raise ValueError("Input must consist of positive integers")
+
+    return len([num for num in integers if len(str(num)) % 2 == 0])
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
diff --git a/challenge-258/steven-wilson/python/ch-2.py b/challenge-258/steven-wilson/python/ch-2.py
new file mode 100644
index 0000000000..f386802d75
--- /dev/null
+++ b/challenge-258/steven-wilson/python/ch-2.py
@@ -0,0 +1,51 @@
+#!/usr/bin/env python3
+
+
+class SetBitSumCalculator:
+    def __init__(self):
+        self.count_indices = dict()
+        self.max_index = 0
+
+    def _count_one_bit_set(self, binary):
+        ''' Count the number of 1-bit sets'''
+        count = 0
+        for b in binary:
+            if b == "1":
+                count += 1
+        return count
+
+    def _populate_count_indices(self, list_length):
+        if list_length > self.max_index:
+            new_indices = range(self.max_index, list_length)
+            binaries = [bin(i) for i in new_indices]
+            one_bit = [self._count_one_bit_set(b) for b in binaries]
+            for num, count in enumerate(one_bit, start=self.max_index):
+                if str(count) in self.count_indices:
+                    self.count_indices[str(count)].append(num)
+                else:
+                    self.count_indices[str(count)] = [num]
+            self.max_index = list_length
+
+    def sum_of_values(self, *integers, k=1):
+        ''' Given an array of integers and an integer k, find the sum of values
+        whose index binary representation has exactly k number of 1-bit set.
+        >>> calculator = SetBitSumCalculator()
+        >>> calculator.sum_of_values(2, 5, 9, 11, 3, k=1)
+        17
+        >>> calculator.sum_of_values(2, 5, 9, 11, 3, k=2)
+        11
+        >>> calculator.sum_of_values(2, 5, 9, 11, 3, k=0)
+        2
+        '''
+        if not isinstance(k, int):
+            raise TypeError("k is not a valid input")
+
+        len_integers = len(integers)
+        self._populate_count_indices(len_integers)
+        return sum(integers[x] for x in self.count_indices[str(k)] if x < len_integers)
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()