Php address reference efficiency)

Copy codeThe Code is as follows:
<? Php
Echo 'in in time: '. $ begin = microtime (false).' <br/> '; // begin to count time
$ Array = array ();
For ($ I = 1; $ I <= 10000; $ I ++) {// generates a large array
$ Array [$ I] = $ I;
}
/*
$ Arr = $ array; // the total time for copying and printing data is 0.02.
Foreach ($ arr as $ ar ){
Echo $ ar. '<br/> ';
}
*/
/*
$ Newarr = & $ array; // address reference time is always controlled within 0.01.
Foreach ($ newarr as $ r ){
Echo $ r. '<br/> ';
}
*/
Foreach ($ array as $ a) {// basically 0.02 is rarely 0.01. Why is there no address reference faster? Wondering
Echo $ a. '<br/> ';
}
Echo 'end time: '. $ end = microtime (false).' <br/> '; // end to count time
Echo 'total time: '. ($ end-$ begin );
?>