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What is the result of the following query?
What is the result of the following query?
declare @a int
declare @b int
set @a = 5
set @b = 11
select @a = @a ^ @b , @b = @b ^ @a, @a = @a ^ @b
print '@a = '+convert(varchar,@a)
print '@b = '+convert(varchar,@b)
Answer
@a = 11 , @b = 5
Explanation
Here is the explanation:
Step 1
@a has the value of 5 and is binairy 101
@b has the value of 11 and is binairy 1011
After “select @a = @a ^ @b , @b = @b ^ @a, @a = @a ^ @b”
the values are
@a will get the value from 101 ^ 1011 = 1110 (=14)
@b have stil the value of 1011 (=11)
Step 2
After “select @a = @a ^ @b , @b = @b ^ @a, @a = @a ^ @b”
The values are
@a will stay at the value 1110 (=14)
@b will get the value from 1011 ^ 1110 = 101 (=5)
Step 3
After “select @a = @a ^ @b , @b = @b ^ @a, @a = @a ^ @b”
@a will get the value from 1110 ^ 101 = 1011 (=11)
@b will stay at the value 101 (=5)
(Continued on next question...)
