Question

How to swap two numbers without using third variable in PHP

Answer 1

$a = 5;
$b = 13;
     
$a = $a + $b;
$b = $a - $b;
$a = $a - $b;

echo "a = " . $a . "<br />";
echo "b = " . $b . "<br />";
 
/*
run:
  
a = 13
b = 5
   
*/

 

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Answer 2

$a = 5;
$b = 13;
     
$a = $a + $b - ($b = $a);

echo "a = " . $a . "<br />";
echo "b = " . $b . "<br />";
 
/*
run:
  
a = 13
b = 5
   
*/

 

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Answer 3

$a = 5;
$b = 13;
     
$a = $a ^ $b;
$b = $a ^ $b;
$a = $b ^ $a;

echo "a = " . $a . "<br />";
echo "b = " . $b . "<br />";
 
/*
run:
  
a = 13
b = 5
   
*/

 

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Answer 4

$a = 5;
$b = 13;
     
$a = $b - ~$a - 1;
$b = $a + ~$b + 1;
$a = $a + ~$b + 1;

echo "a = " . $a . "<br />";
echo "b = " . $b . "<br />";
 
/*
run:
  
a = 13
b = 5
   
*/

 

70+ SQL courses for beginners and professionals