2020-10-25 09:24:35 +00:00
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#!/usr/bin/env python3
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"""Provide the functionality to manipulate a single bit."""
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2020-12-24 12:46:44 +00:00
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def set_bit(number: int, position: int) -> int:
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2020-10-25 09:24:35 +00:00
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"""
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Set the bit at position to 1.
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Details: perform bitwise or for given number and X.
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2024-04-22 19:51:47 +00:00
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Where X is a number with all the bits - zeroes and bit on given
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position - one.
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2020-10-25 09:24:35 +00:00
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>>> set_bit(0b1101, 1) # 0b1111
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15
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>>> set_bit(0b0, 5) # 0b100000
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32
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>>> set_bit(0b1111, 1) # 0b1111
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15
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"""
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return number | (1 << position)
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2020-12-24 12:46:44 +00:00
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def clear_bit(number: int, position: int) -> int:
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2020-10-25 09:24:35 +00:00
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"""
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Set the bit at position to 0.
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Details: perform bitwise and for given number and X.
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2024-04-22 19:51:47 +00:00
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Where X is a number with all the bits - ones and bit on given
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position - zero.
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2020-10-25 09:24:35 +00:00
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>>> clear_bit(0b10010, 1) # 0b10000
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16
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>>> clear_bit(0b0, 5) # 0b0
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0
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"""
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return number & ~(1 << position)
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2020-12-24 12:46:44 +00:00
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def flip_bit(number: int, position: int) -> int:
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2020-10-25 09:24:35 +00:00
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"""
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Flip the bit at position.
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Details: perform bitwise xor for given number and X.
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2024-04-22 19:51:47 +00:00
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Where X is a number with all the bits - zeroes and bit on given
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position - one.
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2020-10-25 09:24:35 +00:00
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>>> flip_bit(0b101, 1) # 0b111
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7
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>>> flip_bit(0b101, 0) # 0b100
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4
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"""
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return number ^ (1 << position)
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def is_bit_set(number: int, position: int) -> bool:
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"""
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Is the bit at position set?
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Details: Shift the bit at position to be the first (smallest) bit.
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Then check if the first bit is set by anding the shifted number with 1.
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>>> is_bit_set(0b1010, 0)
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False
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>>> is_bit_set(0b1010, 1)
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True
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>>> is_bit_set(0b1010, 2)
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False
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>>> is_bit_set(0b1010, 3)
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True
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>>> is_bit_set(0b0, 17)
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False
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"""
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return ((number >> position) & 1) == 1
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2021-05-18 14:54:34 +00:00
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def get_bit(number: int, position: int) -> int:
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"""
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Get the bit at the given position
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Details: perform bitwise and for the given number and X,
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2024-04-22 19:51:47 +00:00
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Where X is a number with all the bits - zeroes and bit on given position - one.
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2021-05-18 14:54:34 +00:00
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If the result is not equal to 0, then the bit on the given position is 1, else 0.
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>>> get_bit(0b1010, 0)
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0
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>>> get_bit(0b1010, 1)
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1
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>>> get_bit(0b1010, 2)
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0
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>>> get_bit(0b1010, 3)
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1
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"""
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return int((number & (1 << position)) != 0)
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2020-10-25 09:24:35 +00:00
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if __name__ == "__main__":
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import doctest
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doctest.testmod()
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