$cup Computer calculation is equal to 13. How to calculate it?
<?php
$x = 5;
$y = ++$x;
$z = $x + $y;
echo "{$z} </ br>";
echo "{$x} </br>";
echo $y;
?>
//You will get a plus sign for $y = ++$x; this code Change to the front and change to the back. Watch for changes. You will understand after thinking about it a few times
<?php $x = 5; $y = 6; $foo = $x++ + $x--; //$x和$y不变 $bar = ++$y + ++$x; //$x=6 $y=7 $cup = $x-- + $y--; //$x和$y不变 6+7=13
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<?php
$x = 5;
$y = ++$x;
$z = $x + $y;
echo "{$z} </ br>";
echo "{$x} </br>";
echo $y;
?>
//You will get a plus sign for $y = ++$x; this code Change to the front and change to the back. Watch for changes. You will understand after thinking about it a few times