$a = "abc";
$b= "def";
$a = $a^$b;
$b = $b^$a;
$a = $a^$b;
echo $b; //abc
echo $a; //def
explain the calculation process, why variables are exchanged
$a = "abc";
$b= "def";
$a = $a^$b;
$b = $b^$a;
$a = $a^$b;
echo $b; //abc
echo $a; //def
explain the calculation process, why variables are exchanged
binary XOR exchange, any language is the same
refer to https://blog.csdn.net/zxm1306.
1^1=0
0^0=0
1^0=1
0^1=1$b^($a^$b)=$a^($b^$b)=$a
$a^($a^$b)=$b^($a^$a)=$bsuppose the binary value of $an is 1000 $b is 1010
// $a,$b
//$a = $a^$b; // 1000 1010
//echo $a; // 0010
//$b = $a^$b; //1010 0010 =1000
//echo $b; //1000
//$a = $a^$b; // 0010 1000 = 1010
//echo $a; // 1010Previous: How node.js reads numbers at a specific location
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