Update count_number_of_one_bits.py

bit_manipulation/count_number_of_one_bits.py

@@ -1,19 +1,51 @@
-def get_set_bits_count(number: int) -> int:
+from timeit import timeit
+
+
+def get_set_bits_count_using_brian_kernighans_algorithm(number: int) -> int:
     """
     Count the number of set bits in a 32 bit integer
-    >>> get_set_bits_count(25)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(25)
     3
-    >>> get_set_bits_count(37)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(37)
     3
-    >>> get_set_bits_count(21)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(21)
     3
-    >>> get_set_bits_count(58)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(58)
     4
-    >>> get_set_bits_count(0)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(0)
     0
-    >>> get_set_bits_count(256)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(256)
     1
-    >>> get_set_bits_count(-1)
+    >>> get_set_bits_count_using_brian_kernighans_algorithm(-1)
+    Traceback (most recent call last):
+        ...
+    ValueError: the value of input must be positive
+    """
+    if number < 0:
+        raise ValueError("the value of input must be positive")
+    result = 0
+    while number:
+        number &= number - 1
+        result += 1
+    return result
+
+
+def get_set_bits_count_using_modulo_operator(number: int) -> int:
+    """
+    Count the number of set bits in a 32 bit integer
+    >>> get_set_bits_count_using_modulo_operator(25)
+    3
+    >>> get_set_bits_count_using_modulo_operator(37)
+    3
+    >>> get_set_bits_count_using_modulo_operator(21)
+    3
+    >>> get_set_bits_count_using_modulo_operator(58)
+    4
+    >>> get_set_bits_count_using_modulo_operator(0)
+    0
+    >>> get_set_bits_count_using_modulo_operator(256)
+    1
+    >>> get_set_bits_count_using_modulo_operator(-1)
     Traceback (most recent call last):
         ...
     ValueError: the value of input must be positive
@@ -28,7 +60,86 @@ def get_set_bits_count(number: int) -> int:
     return result
 
 
+def benchmark() -> None:
+    """
+    Benchmark code for comparing 2 functions,
+    with 3 different length int values.
+    """
+    print("\nFor 25 = :")
+    print(
+        "> get_set_bits_count_using_modulo_operator()",
+        "\t\tans =",
+        get_set_bits_count_using_modulo_operator(25),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_modulo_operator(25)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+    print(
+        "> get_set_bits_count_using_brian_kernighans_algorithm()",
+        "\tans =",
+        get_set_bits_count_using_brian_kernighans_algorithm(25),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_brian_kernighans_algorithm(25)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+
+    print("\nFor 37 = :")
+    print(
+        "> get_set_bits_count_using_modulo_operator()",
+        "\t\tans =",
+        get_set_bits_count_using_modulo_operator(37),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_modulo_operator(37)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+    print(
+        "> get_set_bits_count_using_brian_kernighans_algorithm()",
+        "\tans =",
+        get_set_bits_count_using_brian_kernighans_algorithm(37),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_brian_kernighans_algorithm(37)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+
+    print("\nFor 58 = :")
+    print(
+        "> get_set_bits_count_using_modulo_operator()",
+        "\t\tans =",
+        get_set_bits_count_using_modulo_operator(58),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_modulo_operator(58)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+    print(
+        "> get_set_bits_count_using_brian_kernighans_algorithm()",
+        "\tans =",
+        get_set_bits_count_using_brian_kernighans_algorithm(58),
+        "\ttime =",
+        timeit(
+            "z.get_set_bits_count_using_brian_kernighans_algorithm(58)",
+            setup="import __main__ as z",
+        ),
+        "seconds",
+    )
+
+
 if __name__ == "__main__":
     import doctest
 
+    benchmark()
     doctest.testmod()