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gray_codec.py
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gray_codec.py
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def encode(number):
"""
Find the gray code corresponding to number.
Gray code is an ordering of the binary system
where any two consecutive values differ by
exactly one bit.
For 3-bit numbers, the gray codes are as follows:
000, 001, 011, 010, 110, 111, 101, 100
Denote by G the function mapping binary numbers to
gray codes. In light of the above, G(5) = 7
Time complexity: O(1)
Space complexity: O(1)
"""
return number ^ (number >> 1)
def decode(gray_code):
"""
Decode a gray code back into a number.
Let n be the number of bits of the gray code.
Time complexity: O(n)
Space complexity: O(1)
"""
number = 0
while gray_code:
number = number ^ gray_code
gray_code >>= 1
return number
"""
Below code outputs:
000:000 001:001 010:011 011:010 100:110 101:111 110:101 111:100
"""
for number in range(0, 8):
gray_code = encode(number)
decoded_number = decode(gray_code)
print(f"{decoded_number:03b}:{gray_code:03b}", end=" ")