Just PHP FUN 017.

compose.php

<?php
# https://www.codewars.com/kata/56f253dd75e340ff670002ac Composing squared strings.
function compose($s1, $s2) {
    $a = explode("\n",$s1);
    $b = array_reverse(explode("\n",$s2));
    $size = count($a);
    $answer = "";
    for($i = 0; $i < $size; $i++)
    $answer .= substr($a[$i],0,$i+1).substr($b[$i],0,$size - $i)."\n";
    return trim($answer);
}

dateNbDays.php

<?php
# https://www.codewars.com/kata/569218bc919ccba77000000b Target Date.
function ($a0, $a, $p) {
  $p = $p/36000;
  $date = new DateTime('2016-01-01');
  while($a0 < $a){
    $a0 += $a0*$p;
    $date->modify('+1 day');
  }
  return $date->format('Y-m-d');
}

factorial.php

<?php
# https://www.codewars.com/kata/54ff0d1f355cfd20e60001fc Factorial.
function factorial(int $n): int {
  if(0 > $n || 12 < $n) throw new RangeException("Incorrect input");
  if(0 == $n) return 1;
  return array_product(range(1,$n));
}

just_php_fun_017.md

Just PHP FUN 017.

• https://www.codewars.com/kata/569218bc919ccba77000000b Target Date.
• https://www.codewars.com/kata/56a4872cbb65f3a610000026 Rotate for a Max.
• https://www.codewars.com/kata/56e3cd1d93c3d940e50006a4 How Green Is My Valley?
• https://www.codewars.com/kata/54ff0d1f355cfd20e60001fc Factorial.
• https://www.codewars.com/kata/56f253dd75e340ff670002ac Composing squared strings.

Started at 22:10 06.06.2020 Saturday June.
Finished at 1:45 07.06.2020 Sunday June. (3hrs 35minutes)

makeValley.php

<?php
# https://www.codewars.com/kata/56e3cd1d93c3d940e50006a4 How Green Is My Valley?
function makeValley($a) {
    $x = $a; rsort($x);
    $i = 0; $j = count($a) - 1;
    for($k = 0; $k < count($a); $k+=1){
      if(0 == $k%2){
          $a[$i] = $x[$k]; $i+=1;
        }
      else{
          $a[$j] = $x[$k]; $j -= 1;
      }
    }
    return $a;
}

maxRot.php

<?php
# https://www.codewars.com/kata/56a4872cbb65f3a610000026 Rotate for a Max.
function maxRot($n) {
    $arr = str_split($n);
    $s = count($arr);
    $max = $n;
    for($i = 0; $i < $s; $i +=1){
      $shift = $arr[$i];
      for($j = $i+1; $j < $s; $j +=1) $arr[$j-1] = $arr[$j];
      $arr[$s-1] = $shift;
      $tmp = (int) implode($arr);
      if($tmp > $max) $max = $tmp;
    }
    return $max;
}