13 lines
461 B
Ruby
13 lines
461 B
Ruby
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#Given a number,check if it is power of 2 or not without using division or modulo operator.
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#Algorithm: For any power of 2,say x, the bitwise and of x and x-1 is always 0.
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#e.g. 64 = 1000000, 63= 0111111 now 1000000&0111111==0000000
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def check_power(x)
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if x&(x-1)==0
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print "#{x} is power of two"
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else
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print "#{x} is not power of two"
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end
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end
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check_power(126) # => 126 is not power of two
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check_power(1024) # => 1024 is power of two
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