将多维数组转换为单个数组

can you please help me with my code, I'm having a hard time in transforming my multidimensional array to a single array

this is my multidimensional array:

array:2 [
      0 => array:3 [
        0 => "tuesday"
        1 => "thursday"
      ]
      1 => array:3 [
        0 => "monday"
        1 => "wednesday"
        2 => "friday"
      ]
    ]

this is what I'm trying to do:

array:["tuesday","thursday","monday","wednesday","friday"]

this is my code

$day = [
          0 => array:3 [
            0 => "tuesday"
            1 => "thursday"
          ]
          1 => array:3 [
            0 => "monday"
            1 => "wednesday"
            2 => "friday"
          ]
        ];
$days = [];

$lent = count($day);
        for ($x=0; $x < $lent ; $x++) { 
            $lengt = count($data[$x]);
            for ($i=0; $i < $lengt; $i++) { 
                $days[$x] = $day[$x][$i];
            }
        }

Easy:

$flattened = [];
foreach ($mdarray as $arr) {
    foreach ($arr as $val) {
        $flattened[] = $val;
    }
}

What the above code does is it iterates through the multi-dimensional array, gets the value of each subarray, and adds its elements to $flattened.

If you're using PHP 5.6+, this code is simpler:

$flattened = array_merge(...$mdarray);

for($i = 0; $i < count($day); $i++){
    for($j = 0; $j < count($day[$i]); $j++){
        $days[] = $day[$i][$j];
    }
}

call_user_func_array To combine several results .

$oneDimensionalArray = call_user_func_array('array_merge',$day);