How to use array_push with associative array and index key?

Question

I am a bit 'rusty with php as it happens that sometimes I use it for weeks and sometimes it happens that you do not use for months. Either way I'm trying to pass values of another array are "array", on another array in an orderly manner ... What I want to do is essentially create a key that allows me to organize incremental values per line, in particular;

array content

Array 
(
    [key] => value
    [2] => 1 
    [3] => Inter 
    [4] => 4 
    [5] => 4 
    [6] => 0 
    [7] => 0 
    [8] => 5 
    [9] => 1
    [10] => +4
    [11] => 12
    [12] => Chievo Verona - Inter 0 - 1
    [13] => Inter - Milan 1 - 0
    [14] => Carpi - Inter 1 - 2
    [15] => Inter - Atalanta 1 - 0
    [16] => ;
    [17] => 2
    [18] => Torino
    [19] => 4
    [20] => 3
    [21] => 1
    [22] => 0
    [23] => 9
    [24] => 4
    [25] => +5
    [26] => 10
    [27] => Torino - Sampdoria 2 - 0
    [28] => Hellas Verona - Torino 2 - 2
    [29] => Torino - Fiorentina 3 - 1
    [30] => Frosinone - Torino 1 - 2
    [31] => ;
    [32] => 3
    [33] => Fiorentina
    [34] => 4
    [35] => 3
    [36] => 0
    [37] => 1
    [38] => 5
    [39] => 3
    [40] => +2
    [41] => 9
    [42] => Carpi - Fiorentina 0 - 1
    [43] => Fiorentina - Genoa 1 - 0
    [44] => Torino - Fiorentina 3 - 1
    [45] => Fiorentina - Milan 2 - 0
    [46] => ;
    [47] => 4
    [48] => Roma
    [49] => 4
    [50] => 2 

the ";" It'll need to be able to recognize where you break the line, I do not remember if there is any method that allows me to access the next key.

Currently my code is:

$classifica = array("key" => "value");
function buildArrayClassifica()
{
    global $array; 
    global $classifica;

    $i = 0; 

    foreach(array_slice($array,1)  as $key => $value) 
    {
        if($value != ";")
        {
            array_push($classifica[$i], $value); //there is a problem
            echo $value . " ";
        }
        else if($value == "value ")
        {
            continue;
        }
        else
        {
            $i++;         
            echo "<br/>";
        }
    }
}

The code I will return this error:

Warning: array_push () Expects parameter 1 to be array, null given in...

in particular on array_push, it seems not to accept incremental keys or maybe I'm doing it the wrong way. Can anyone tell me how to solve?

UPDATING

As you have seen the issue is not simple and it is quite difficult to explain the problem, but I will try to be even clearer to meet. As you can see above you are the structure of the array "array", but is a disordered structure that needs to be ordered in an additional array. To recapitulate the structure of the array "array" is:

1 , Inter , 4 , 4 , 0 , 0 , 5 , 1 , +4 , 12 , Chievo Verona - Inter 0 - 1 , Inter - Milan 1 - 0 , Carpi - Inter 1 - 2 , Inter - Atalanta 1 - 0 , ;

the ";" means that the line is finished. So the next value near the ";" means that a new line coming. What I need is move all the value of "array" in array classifica, but I want organize them for:

ROW1 =>  1 , Inter , 4 , 4 , 0 , 0 , 5 , 1 , +4 , 12 , Chievo Verona - Inter 0 - 1 , Inter - Milan 1 - 0 , Carpi - Inter 1 - 2 , Inter - Atalanta 1 - 0 
ROW2 => Other values...

So the ROW1, 2 .. rapresents the key of the array classifica. I'm trying to push the value inside a row and after it increment $i index but the code doesn't add the value because the index replace in loop the actual key, for example:

actual foreach content:
$i = 0
value = "Inter"
content of array=> [0] => Inter
now the $i is ever 0 because the row isn't finished yet, the ";" 
it has not yet been reached, so the next content of foreach is:
"1" but replace the "Inter" value, so this is a problem.

Answer 1

You cannot use array_push() in this way. Please try:

$classifica = array();
function buildArrayClassifica()
{
    global $array; 
    global $classifica;

    $i = 0; 

    foreach(array_slice($array,1) as $key => $value) 
    {
        if($value != ";")
        {
            $classifica[$i] = $value;
            echo $value . " ";
        }
        else if($value == "value ")
        {
            continue;
        }
        else
        {
            $i++;         
            echo "<br/>";
        }
    }
}

This will create indexes (the value of $i) when $value is added to your array. array_push() would place the $value at the next numerical index and may not be what you want by the looks of it. You could also use $key if you wanted the index to match.

EDIT

After more discussion, you have a specific format, where the first Item is the Key, the following indexes are values, and when you encounter the value ";", it starts the sequence over. So when we read:

[2] => 1 
[3] => Inter 
[4] => 4 
[5] => 4 
[6] => 0 
[7] => 0 
[8] => 5 
[9] => 1
[10] => +4
[11] => 12
[12] => Chievo Verona - Inter 0 - 1
[13] => Inter - Milan 1 - 0
[14] => Carpi - Inter 1 - 2
[15] => Inter - Atalanta 1 - 0
[16] => ;

The first value, '1' is our Index, the following values become the Value for this Index, and we stop reading when we find ";". That would look something like:

<?php
function buildArrayClassifica($dataArray){
    $resultArray = array();
    $t = array_values($dataArray);
    print_r($t);
    $lsc = 0;
    foreach($t as $k => $v){
        if((string)$v == ';'){
            echo "<p>Found ';' at [$k] => {$v}</p>";
            // Found end of data
            // Save position
            $scp = $k;
            echo "<p>Recorded [$scp] position for ';'.</p>";
            // Reset to find the Index, first int in this series
            $c=$lsc; // First pass this should be 0
            // Set the index
            if($lsc ==0){
                // First pass
                $index = intval($t[$c]);
                echo "<p>Getting Index from position [" . ($c) ."] => $index for Result Array.</p>";
                $c++;
            } else {
                $c++;
                $index = intval($t[$c]);
                echo "<p>Getting Index from position [" . ($c) ."] => $index for Result Array.</p>";
                $c++;
            }
            echo "<p>Starting to read data from [$c] until [$scp].</p>";
            // Init implode variable
            $data = "";
            for($c;$c<$scp;$c++){
                //Populate variable with the series up to semicolon, skipping first element (index)
                $data .= $t[$c] . ", ";
            }
            echo "<p>Data collected for this round: '" . htmlentities(substr($data,0,-2)) . "'</p>";
            // populate result array
            $resultArray[$index] = substr($data,0,-2);
            echo "<p>resultArray[$index] => " . htmlentities($resultArray[$index]) . "</p><br />";
            $lsc = $scp;
        }
    }

    return $resultArray;
}
$oldArray = array(1, "Inter", 4 , 4 , 0 , 0 , 5 , 1 , "+4" , 12 , "Chievo Verona - Inter 0 - 1", "Inter - Milan 1 - 0", "Carpi - Inter 1 - 2", "Inter - Atalanta 1 - 0", ";", 2, "Torino", 4, 3, 1, 0, 9, 4, '+5', 10, "Torino - Sampdoria 2 - 0", "Hellas Verona - Torino 2 - 2", "Torino - Fiorentina 3 - 1", "Frosinone - Torino 1 - 2", ";", 3, "apple", 0, 4, 6, "apple", ";");

$classifica = buildArrayClassifica($oldArray);
print_r($classifica);
?>

My initial testing seems to work for what you described. The first element of the array becomes the Index, the next few values become imploded until we reach the semicolon (;) value.

What I see as a result:

Array ( [1] => Inter, 4, 4, 0, 0, 5, 1, +4, 12, Chievo Verona - Inter 0 - 1, Inter - Milan 1 - 0, Carpi - Inter 1 - 2, Inter - Atalanta 1 - 0 [2] => Torino, 4, 3, 1, 0, 9, 4, +5, 10, Torino - Sampdoria 2 - 0, Hellas Verona - Torino 2 - 2, Torino - Fiorentina 3 - 1, Frosinone - Torino 1 - 2 [3] => apple, 0, 4, 6, apple ) 

ASIDE

If it were me, I would push it all into an array like so:

$data = array();
for($c;$c<$scp;$c++){
    $data[] = $t[$c];
}
$resultArray[$index] = $data;

Or if you really want a string:

$resultArray[$index] = implode(", ", $data);

Hope that helps.