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34 lines
503 B
Plaintext
Executable File
34 lines
503 B
Plaintext
Executable File
BIT-WISE
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1. To find a number:
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11000101 is 2^0+2^2+2^6+2^7 = 197
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2. Left shifting:
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0010 1011 << 4 ---> 1011 000
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3. Right shifting:
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0010 1011 >> 4 ---> 0000 0010
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or it can be filled with the copy of the first bit, instead of 0:
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1011 0010 >> 4 ---> 1111 1011
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4. XOR can cancels out:
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15 ^ 12 ^ 15 = 12
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5. 2^x:
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left-shift 1 by x:
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0000 0001 << x
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so if x = 2, 2^2 = 4 -> 100
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0000 0001 << 2 ---> 0000 0100
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6. Is power of 2?
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just do x&(x-1).
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if 0 --> yes!
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