Just PHP FUN 050.

digit_degree.php

<?php
# https://www.codewars.com/kata/589422431a88082ea600002a Simple Fun #75: Digit Degree.
function digit_degree($n) {
  $sum = function($x){ return array_sum(str_split($x));};
  $cnt = 0;
  while($sum($n) != $n){ $cnt += 1; $n = $sum($n);}
  return $cnt;
}

html_end_tag_by_start_tag.php

<?php
# https://www.codewars.com/kata/5886f3713a111b620f0000dc Simple Fun #28: Html End Tag By Start Tag.
function html_end_tag_by_start_tag(string $start_tag): string {
  $x = [];
  preg_match('/<([^\s>]+)/',$start_tag,$x);
  return '</'.$x[1].'>';
}

just_php_fun_050.md

Just PHP FUN 050.

• https://www.codewars.com/kata/58a3c1f12f949e21b300005c Simple Fun #124: Lamps.
• https://www.codewars.com/kata/589422431a88082ea600002a Simple Fun #75: Digit Degree.
• https://www.codewars.com/kata/5886f3713a111b620f0000dc Simple Fun #28: Html End Tag By Start Tag.
• https://www.codewars.com/kata/5886da134703f125a6000033 Simple Fun #24: Pages Numbering with Ink.
• https://www.codewars.com/kata/58846d50f54f021d90000012 Simple Fun #17: Rounders.

Started at 21:42 15.07.2020 Wednesday July.
Finished at 23:42 15.07.2020 Wendesday July. (2hrs 00minutes)

lamps.php

<?php
# https://www.codewars.com/kata/58a3c1f12f949e21b300005c Simple Fun #124: Lamps.
function lamps(array $a): int {
  // count if first shine. even == 1, odd == 0
  $cnt_even = 0;
  // count if first off. even == 0, odd == 1
  $cnt_odd = 0;
  foreach($a as $i=>$x){
    if( 0 == $i % 2){
       if(0 == $x) $cnt_even += 1;
       if(1 == $x) $cnt_odd += 1;
    }else{
      if(0 == $x) $cnt_odd += 1;
      if(1 == $x) $cnt_even += 1;
    }
  }
  return min($cnt_even,$cnt_odd);
}

pages_numbering_with_ink.php

<?php
#  https://www.codewars.com/kata/5886da134703f125a6000033 Simple Fun #24: Pages Numbering with Ink.
function pages_numbering_with_ink(int $current, int $number_of_digits): int {
  while( 0 <= $number_of_digits - floor(log10($current)) - 1){ 
    $number_of_digits -= floor(log10($current)) + 1;
    $current += 1; 
  }
  return $current - 1;
}

rounders_.php

<?php
# https://www.codewars.com/kata/58846d50f54f021d90000012 Simple Fun #17: Rounders.
function rounders(int $value): int {
  echo "Start: $value \n";
  while(!preg_match('/^[^0]0*$/',$value)){
    $z = preg_replace('/^.*([^0]0*)$/','$1',$value);
    // echo "z = $z \n";
    $value -= (int) $z;
    if($z[0] >= 5){
      $z =  10**strlen($z);
      //echo "Addin z = $z \n";
      $value += $z;
    }
    echo "$value \n";
  } 
  return $value;
}


class RoundersTest extends TestCase {
  public function testBasic() {
    $this->assertEquals(20, rounders(15));
    $this->assertEquals(1000, rounders(1234));
    $this->assertEquals(2000, rounders(1445));
    $this->assertEquals(10, rounders(14));
    $this->assertEquals(100, rounders(99));
    $this->assertEquals(10, rounders(10));
    $this->assertEquals(70000000, rounders(69019657));
  }
}