solution('abc') // should return ['ab', 'c_'] solution('abcdef') // should return ['ab', 'cd', 'ef']

Split Strings

//solution('abc') should return ['ab', 'c_']
//solution('abcdef') should return ['ab', 'cd', 'ef']

function solution($str) {

  $STR = str_split($str, 2);

	foreach($STR as $key => $value){
	  
		$value = str_pad($value, 2, "_", STR_PAD_RIGHT);
		$STR[$key] = $value;
	}
  return $STR;
}