How to remove duplicate values from an array in PHP

Question

How can I remove duplicate values from an array in PHP?

Answer 1

I have done this without using any function.

$arr = array("1", "2", "3", "4", "5", "4", "2", "1");

$len = count($arr);
for ($i = 0; $i < $len; $i++) {
  $temp = $arr[$i];
  $j = $i;
  for ($k = 0; $k < $len; $k++) {
    if ($k != $j) {
      if ($temp == $arr[$k]) {
        echo $temp."
";
        $arr[$k]=" ";
      }
    }
  }
}

for ($i = 0; $i < $len; $i++) {
  echo $arr[$i] . " 

";
}