Just PHP FUN 118.

CaesarCipher.php

<?php
# https://www.codewars.com/kata/526d42b6526963598d0004db Caesar Cipher Helper.
class CaesarCipher {
  public $ch2n = ['A'=>1,'B'=>2,'C'=>3,'D'=>4,'E'=>5,'F'=>6,'G'=>7,'H'=>8,'I'=>9,'J'=>10,'K'=>11,'L'=>12,'M'=>13,'N'=>14,'O'=>15,'P'=>16,'Q'=>17,'R'=>18,'S'=>19,'T'=>20,'U'=>21,'V'=>22,'W'=>23,'X'=>24,'Y'=>25,'Z'=>26,];
  public $n2ch = [1=>'A',2=>'B',3=>'C',4=>'D',5=>'E',6=>'F',7=>'G',8=>'H',9=>'I',10=>'J',11=>'K',12=>'L',13=>'M',14=>'N',15=>'O',16=>'P',17=>'Q',18=>'R',19=>'S',20=>'T',21=>'U',22=>'V',23=>'W',24=>'X',25=>'Y',26=>'Z',];
  public $num = 0;
  function __construct($n){ $this->num = $n;} 
  public function encode($str){
    $answer = ""; $size = strlen($str);
    $str = strtoupper($str);
    for($i = 0; $i < $size; $i +=1) 
      if(preg_match('/[A-Z]/',$str[$i])){
        $answer .= $this->n2ch[($this->ch2n[$str[$i]] + $this->num - 1) % 26 + 1];
      }else{
        $answer .= $str[$i];
      }
    return $answer;
  }
   public function decode($str){
    $answer = ""; $size = strlen($str);
    $str = strtoupper($str);
    for($i = 0; $i < $size; $i +=1) 
      if(preg_match('/[A-Z]/',$str[$i])){
        $number = $this->ch2n[$str[$i]] - 1;
        $number = (26 + $number - $this->num)%26 + 1;
        $answer .= $this->n2ch[$number];
      }else{
        $answer .= $str[$i];
      }
    return $answer;
  }
}

just_php_fun_118.md

Just PHP FUN 118.

• https://www.codewars.com/kata/526d42b6526963598d0004db Caesar Cipher Helper.

Started at 21:21 02.10.2020 Friday Oct.
Finished at 21:51 02.10.2020 Friday Oct. (0hrs 30minutes)