How to remove spaces in front of the second words in search result link?

I am trying to create dynamic searchable keywords for articles. I am replacing spaces with + and generating links like google does example: search?q=text1+text2+text My code generate first link same as link in example, but adding + to in front of the second link like this:

Fisrt Link (which is what I want):

search?q=text1+text2+text

Second Link (Which is not right):

search?q=+text1+text2+text

Adding a + between ?q=+text

how can I remove that space from in front of the second keyword ?

I tried several ways but all did different things accept what I want.

Here is my code:

$keywords = "text1 text2 text3, text4 text5 text6";
$tag = explode(",",$keywords); 
for ($i=0; $i<count($tag);$i++){
    $cat = str_replace(" ", "+", $tag[$i]);
    echo "<a href=\"services/?q=".htmlspecialchars($cat)."\"><span itemprop=\"description\">".str_replace("+"," ", htmlspecialchars($cat))."</span></a>";
    echo "<span class=\"separator\">|</span>\n";
}

I would like to generate all links like this:

search?q=text1+text2+text

The trim function removes spaces from the begin and end of a string.

Inserted into your not further changed code:

$keywords = "text1 text2 text3, text4 text5 text6";
$tag = explode(",",$keywords);
for ($i=0; $i<count($tag);$i++){
  $cat = str_replace(" ", "+", trim($tag[$i]));
  echo "<a href=\"services/?q=".htmlspecialchars($cat)."\"><span itemprop=\"description\">".str_replace("+"," ", htmlspecialchars($cat))."</span></a>";
  echo "<span class=\"separator\">|</span>\n";
}