1$arrayMult = [ ['a','b'] , ['c', 'd'] ];
2$arraySingle = call_user_func_array('array_merge', $arrayMult);
3// $arraySingle is now = ['a','b', 'c', 'd'];
1$singleArray = [];
2foreach ($parentArray as $childArray)
3{
4 foreach ($childArray as $value)
5 {
6 $singleArray[] = $value;
7 }
8}
9