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| 1 | +#!/usr/bin/env python3 |
| 2 | + |
| 3 | +"""Provide the functionality to manipulate a single bit.""" |
| 4 | + |
| 5 | + |
| 6 | +def set_bit(number: int, position: int): |
| 7 | + """ |
| 8 | + Set the bit at position to 1. |
| 9 | +
|
| 10 | + Details: perform bitwise or for given number and X. |
| 11 | + Where X is a number with all the bits – zeroes and bit on given |
| 12 | + position – one. |
| 13 | +
|
| 14 | + >>> set_bit(0b1101, 1) # 0b1111 |
| 15 | + 15 |
| 16 | + >>> set_bit(0b0, 5) # 0b100000 |
| 17 | + 32 |
| 18 | + >>> set_bit(0b1111, 1) # 0b1111 |
| 19 | + 15 |
| 20 | + """ |
| 21 | + return number | (1 << position) |
| 22 | + |
| 23 | + |
| 24 | +def clear_bit(number: int, position: int): |
| 25 | + """ |
| 26 | + Set the bit at position to 0. |
| 27 | +
|
| 28 | + Details: perform bitwise and for given number and X. |
| 29 | + Where X is a number with all the bits – ones and bit on given |
| 30 | + position – zero. |
| 31 | +
|
| 32 | + >>> clear_bit(0b10010, 1) # 0b10000 |
| 33 | + 16 |
| 34 | + >>> clear_bit(0b0, 5) # 0b0 |
| 35 | + 0 |
| 36 | + """ |
| 37 | + return number & ~(1 << position) |
| 38 | + |
| 39 | + |
| 40 | +def flip_bit(number: int, position: int): |
| 41 | + """ |
| 42 | + Flip the bit at position. |
| 43 | +
|
| 44 | + Details: perform bitwise xor for given number and X. |
| 45 | + Where X is a number with all the bits – zeroes and bit on given |
| 46 | + position – one. |
| 47 | +
|
| 48 | + >>> flip_bit(0b101, 1) # 0b111 |
| 49 | + 7 |
| 50 | + >>> flip_bit(0b101, 0) # 0b100 |
| 51 | + 4 |
| 52 | + """ |
| 53 | + return number ^ (1 << position) |
| 54 | + |
| 55 | + |
| 56 | +def is_bit_set(number: int, position: int) -> bool: |
| 57 | + """ |
| 58 | + Is the bit at position set? |
| 59 | +
|
| 60 | + Details: Shift the bit at position to be the first (smallest) bit. |
| 61 | + Then check if the first bit is set by anding the shifted number with 1. |
| 62 | +
|
| 63 | + >>> is_bit_set(0b1010, 0) |
| 64 | + False |
| 65 | + >>> is_bit_set(0b1010, 1) |
| 66 | + True |
| 67 | + >>> is_bit_set(0b1010, 2) |
| 68 | + False |
| 69 | + >>> is_bit_set(0b1010, 3) |
| 70 | + True |
| 71 | + >>> is_bit_set(0b0, 17) |
| 72 | + False |
| 73 | + """ |
| 74 | + return ((number >> position) & 1) == 1 |
| 75 | + |
| 76 | + |
| 77 | +if __name__ == "__main__": |
| 78 | + import doctest |
| 79 | + |
| 80 | + doctest.testmod() |
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