「道なりの亀」という問題をPHPで解いてみた。
こんなの1時間で出来るもんなの...?
Kame.php

<?php


class Kame {

	public $map = [ 
		  'ABCDEFGHIJK'
		, 'LMNOPQRSTUV'
		, 'WXYZabcdefg'
		, 'hij'
		, 'klm'
		, 'nop'
		, 'qrs'
		, 'tuv'
		, 'wxy'
		, 'z01'
		, '234'
		, '567'
	];

	private $dirTo = [[1,0],[0,1],[-1,0],[0,-1]]; // 移動量
	private $dir = 0; // 移動方向 右下左上

	public $masu = 'A';
	private $posX = 0;
	private $posY = 0;

	public function init() {
		$htis->masu = 'A';	
		$this->posX = 0;
		$this->posY = 0;
		return $this;
	}

	public function run($command) {
		foreach (str_split($command) as $val) {

			if (preg_match('/[0-9a-f]/', $val) > 0) {
				if ($this->forward($val) === false) {
					break;
				}
			}
			else if (preg_match('/[L|R]/', $val) > 0) {
				$this->rotate($val);
			}
		}
		return $this->masu;
	}

	private function forward($val) {

		$num = hexdec($val);

		// 現在のマスが取得できる間進む
		for ($i = 0; $i < $num; $i++) {

			$mv = $this->dirTo[$this->dir];
			$this->posX += $mv[0] != 0 ? $mv[0] : 0;
			$this->posY += $mv[1] != 0 ? $mv[1] : 0;

			// 7,6,5 から g,f,e へワープ
			if ( count($this->map) <= $this->posY ) {
				$this->posX = (strlen($this->map[0])-$this->posX-1);
				$this->posY = 2;
				$this->rotate('L')->rotate('L');
			}
			// g,f,e から 7,6,5 へワープ
			else if ($this->posY === 3 && $this->posX >= 8) {
				$this->posX = (strlen($this->map[0])-$this->posX-1);
				$this->posY = count($this->map)-1;
				$this->rotate('L')->rotate('L');
			}

			// 現在マスを更新する
			if ($this->update() === false) {
				return false;
			}

		}

		return true;
	}

	private function rotate($val) {
		$this->dir += $val === 'R' ? +1 : -1;
		$this->dir = count($this->dirTo) <= $this->dir 
						? 0 
						: ($this->dir < 0 ? count($this->dirTo)-1 :$this->dir );
		return $this;
	}	

	private function update() {

		if ($this->posX === -1 || $this->posY === -1) {
			$this->masu .= '?';
			return false;
		}

		$masu = substr($this->map[$this->posY], $this->posX, 1);
		if ($masu !== false) {
			$this->masu .= $masu;
			return true;
		}
		else {
			$this->masu .= '?';
			return false;
		}

	}

	public function getMasu() {
		return $this->masu;
	}

}



$testdata = array(
	  array('2RcL3LL22','ABCNYjmpsvy147edcbcdef')
	, array('L3R4L5RR5R3L5','A?')
	, array('2ReLLe','ABCNYjmpsvy147eTITe741yvspmjYNC')
	, array('1ReRRe','ABMXilorux036fUJUf630xuroliXMB')
	, array('ReRRe','ALWhknqtwz25gVKVg52zwtqnkhWLA')
	, array('f','ABCDEFGHIJK?')
	, array('Rf','ALWhknqtwz25gVK?')
	, array('1Rf','ABMXilorux036fUJ?')
	, array('2Rf','ABCNYjmpsvy147eTI?')
	, array('aR1RaL1LaR1R2L1L2','ABCDEFGHIJKVUTSRQPONMLWXYZabcdefg567432')
	, array('2R1R2L1L2R1R2L1L2R1R2L1L2R1R2L1L2','ABCNMLWXYjihklmponqrsvutwxy')
	, array('2R4R2L4L2R4R2L4L2R4R2L4L2','ABCNYjmlknqtwxy147efgVK?')
	, array('R1L2R4R2L4L2R4R2L4L2R4R2L4L2','ALMNYjmponqtwz0147eTUVK?')
	, array('R2L2R4R2L4L2R4R2L4L2R4R2L4L2','ALWXYjmpsrqtwz2347eTIJK?')
	, array('R3L2R4R2L4L2R4R2L4L2R4R2L4L2','ALWhijmpsvutwz2567eTI?')
	, array('R5L2L5L1LaR1L4L5','ALWhknopmjYNCBMXilorux0325gVKJIHGF')
	, array('1R2L4L2R4R2L4L2R4','ABMXYZabQFGHIJUfg?')
	, array('2R2L4L2R4R2L4L2R4','ABCNYZabcRGHIJKVg?')
	, array('3R2L4L2R4R2L4L2R4','ABCDOZabcdSHIJK?')
	, array('4R2L4L2R4R2L4L2R4','ABCDEPabcdeTIJK?')
	, array('5R2L4L2R4R2L4L2R4','ABCDEFQbcdefUJK?')
	, array('LLL1RRR1LLL1RRR2R1','ALMXYZ?')
	, array('R3RRR3','ALWhij?')
	, array('1LLL4RRR1LR1RL1','ABMXilm?')
	, array('R2L1R2L1R3R4','ALWXilmpsvut?')
	, array('7R4f47LLLc6R9L','ABCDEFGHSd?')
	, array('5RR868L8448LL4R6','ABCDEFEDCBA?')
	, array('42Rd1RLLa7L5','ABCDEFGRc?')
	, array('RRLL6RLR1L5d12LaLRRL529L','ABCDEFGRSTUV?')
	, array('RLR7L6LL1LRRRcRL52R','ALWhknqtuv?')
	, array('1RLR8RLR1R437L99636R','ABMXiloruxwtqnkhWLA?')
	, array('LLL2L3La9Le5LRR','ALWXYZOD?')
	, array('R1LcRR491','ALMNOPQRSTUV?')
	, array('R8L1R1R512L8RLLReRf','ALWhknqtwx0z?')
	, array('1RcL8f1L29a5','ABMXilorux036fedcbaZYXW?')
	, array('R822LeL46LL39LL','ALWhknqtwz25gfedcbaZYXW?')
	, array('9R3L5LRRLb5R3L7cLLLR4L','ABCDEFGHIJUf65?')
	, array('7LLRRR2R3R69Lf76eR2L','ABCDEFGHSdcbaPE?')
	, array('8RRRLL3Le','ABCDEFGHITe765?')
	, array('8R5RLL6LbL4LL5bL','ABCDEFGHITe7410z?')
	, array('6LR2R1LR5LRLRL484L63','ABCDEFGHITe741yxw?')
);

function test($command, $out) {
	$kame = new Kame();
	if ($kame->run($command) === $out) {
		echo "OK \n";
	}
	else {
		echo "NG $command, $out (".$kame->getMasu().") \n";
	}
}

function testall($testdata) {
	foreach ($testdata as $data) {
		test($data[0], $data[1]);	
	}
}

testall($testdata);