我有这样的代码如何代码打印像这样？

Question

input name: DEVO AVIDIANTO PRATAMA output: DAP if the input three word , appears DAP

input name: AULIA ABRAR output: AAB if the input two words, appears AAB

input name: AULIA output: AUL   if the input one word, appears AUL

<?php
$nama = $_POST['nama'];
$arr = explode(" ", $nama);
//var_dump($arr);die;
$jum_kata = count($arr);
//echo $jum_kata;die;
$singkatan = "";
if($jum_kata  == 1){
  //print_r($arr);
  foreach($arr as $kata)
  {
  echo substr($kata, 0,3);
  }
}else if($jum_kata == 2) {
  foreach ($arr as $kata) {
    echo  substr($kata,0,2);
  }
}else {

  foreach ($arr as $kata) {
    echo  substr($kata,0,1);
  }

}

?>

how to correct this code :

else if($jum_kata == 2) {
  foreach ($arr as $kata) {
    echo  substr($kata,0,2);
  }

to print AAB?

Answer 1

As a variant of another approach. Put each next string over the previous with one step shift. And then slice the start of a resulting string

function initials($str, $length=3) {
  $string = '';
  foreach(explode(' ', $str) as $k=>$v) {
    $string = substr($string, 0, $k) . $v;
  }  
  return substr($string, 0, $length);
}

echo initials('DEVO AVIDIANTO PRATAMA'). "
"; // DAP
echo initials('AULIA ABRAR'). "
";            // AAB
echo initials('AULIA'). "
";                  // AUL

demo