# Define lowbit (x) & amp; (-x,

# Define lowbit (x) & (-x) Principle details,

# Define lowbit (x) & (-x ))

It can also be written as follows:

Int Lowbit (x ){

Return x & (-x );

}

For example:

1> x = 1:

Convert decimal to binary (8 digits ):

1 => 0000 0001

-1 => 1111 1111(Here is the complement of 1)

1 & (-1 ):

2> x = 6:

Convert decimal to binary (8 digits ):

6 => 0000 0110

-6 => 1111 1010(Here is the complement Code of 6)

6 & (-6 ):

So 6 & (-6) = 2

Summary:

Obtain 2 ^ p (where p: x represents the first position of 1 in the right direction of the number ),

For example, if the binary value of 6 is 110, the zeroth to the left is 0, and the first is 1, p = 1,

Therefore, Lowbit (6) = 2 ^ 1 = 2.

It can be directly understood as: Binary bitwise and operation, returns the maximum power factor of 2 not greater than x

StartAt: 2016-03-18, 16:37:32