PHP implementation Two-way merge sort

1 $arr= [9, 43, 12, 0, 87, 1];2 functionMerge_sort (&$arr){3_merge_sort ($arr,$arr, 0,Count($arr)-1);4 }5 6 function_merge_sort (&$s _arr, &$d _arr,$i,$j){7     if($i>$j){8         return;9     }Ten     if($i==$j){ One         Echo' AA '; A         $d _arr[$i] =$s _arr[$i]; -         return false; -     } the     $tmp _arr=Array(); -     $m=intval(($i+$j)/2); -     Echo $m; -     if($i<=$m){ +_merge_sort ($s _arr,$tmp _arr,$i,$m); -     } +     if($m+1 <=$j ){ A_merge_sort ($s _arr,$tmp _arr,$m+1,$j); at     } -Merge$tmp _arr,$d _arr,$i,$m,$j); - } -$s _arr in $start to $m and $m to $end two sequences are ordered, merging the two sequences into $d_arr - functionMerge (&$s _arr, &$d _arr,$start,$m,$end){ -     $i=$start;$j=$m+1;$d _i=$i; in      while($i<=$m&&$j<=$end){ -         if($s _arr[$i] >$s _arr[$j]){ to             $d _arr[$d _i++] =$s _arr[$i++]; +             //$i + +; -}Else{ the             $d _arr[$d _i++] =$s _arr[$j++]; *         } $     }Panax Notoginseng      while($i<=$m){ -         $d _arr[$d _i++] =$s _arr[$i++]; the         //$i + +; +     } A      while($j<=$end) { the         $d _arr[$d _i++] =$s _arr[$j++]; +     } -}

PHP implementation Two-way merge sort