Question

Here is what I am doing (php)

<?php

for($i = 0; $i <= 30; $i+2)
{
  echo $i;
}
?>

It drives me nuts,coz it does not work [prints nothing, browser keeps trying to load]. But if I change $i+2 to $i++, it works, and if I change it to $i+1, that does not work either.

I am out of my wits. What is going wrong?

Answer 1

It drives me nuts,coz it does not work [prints nothing, browser keeps trying to load]. But if I change $i+2 to $i++, it works, and if I change it to $i+1, that does not work either.

$i++ is equivalent to $i = $i + 1, note the assignment operator =, it isn’t present here $i + 2 adds but doesn’t update …

since $i is never updated, you have an infinite loop, where the script will probably reach the allowable time for processing and terminate.

http://php.net/manual/en/function.set-time-limit.php

Set the number of seconds a script is allowed to run. If this is reached, the script returns a fatal error. The default limit is 30 seconds or, if it exists, the max_execution_time value defined in the php.ini.