如何在PHP中将前两个单词移到后面的两个单词？

Question

I know this is kinda weird, but I need this to complete my task .

I want to move the first two words to the two words thereafter, example is in my (error) code :

<?
$sentence = "zero one two three four five six seven eight";
$sentence2 = explode (" ",$sentence);
$total = count($sentence2);
for ($i = 4; $i < $total; ++$i) {
$result = $sentence2[2]." ".$sentence2[3]." ".$sentence2[0]." ".$sentence2[1]."  ".$sentence2[$i];
}
echo "Original sentence : ".$sentence;
echo "<br>Result : ".$result;
?>

but the result from that code is not what i want, the result is

two three zero one eight

i want the result :

two three zero one four five six seven eight

can you help me make a better code?

Answer 1

Each time the code inside your loop runs, the $result variable receives a new value.

You should only append words at the end of the sequence to it.

So, replace you for loop by this:

$result = $sentence2[2]." ".$sentence2[3]." ".$sentence2[0]." ".$sentence2[1];
for ($i = 4; $i < $total; ++$i) {
    $result .= "  ".$sentence2[$i];
}

Answer 2

You can also use array_splice for this case

$sentence = "zero one two three four five six seven eight";
$words    = explode(" ",$sentence,3);
$base     = explode(" ",$words[2]);
array_splice($base,2,0,array($words[0],$words[1]));
echo implode(" ",$base);

or one line solution,:-)

echo preg_replace('#^(\w+\s+)(\w+\s+)(\w+\s+)(\w+\s+)#','$3$4$1$2',$sentence);

Answer 3

The problem is that you overwrite the result all the time. So when it steps through your for-loop the first time the string will be

two three zero one five

The second time it will be

two three zero one six

etc.

But you will only see it ending by eight because you output the string only at the end. You should store your new string in a variable and append your next number to that. It should read something like;

<?
$sentence = "zero one two three four five six seven eight";
$sentence2 = explode (" ",$sentence);
$total = count($sentence2);
$result = $sentence2[2]." ".$sentence2[3]." ".$sentence2[0]." ".$sentence2[1]."  ";
for ($i = 4; $i < $total; ++$i) {
$result = $result."  ".$sentence2[$i];
}
echo "Original sentence : ".$sentence;
echo "<br>Result : ".$result;
?>

Answer 4

This does the trick nicely.

$sentence = "zero one two three four five six seven eight";
$sentenceParts = explode (" ",$sentence);

$itemCount = count($sentenceParts);
$result = $sentenceParts[2]." ".$sentenceParts[3]." ";
for($i = 0; $i < $itemCount; $i++) {
    if($i != 2 && $i !=3) {
        $result .= $sentenceParts[$i]." ";
    }
}

echo $result;