Grim string to number

PHP CHARS ASCII

<?
    $num_to_char = array(
        '27'    => "1",
        '28'    => "2",
        '29'    => "3",
        '30'    => "4",
        '31'    => "5",
        '32'    => "6",
        '33'    => "7",
        '34'    => "8",
        '35'    => "9",
        '36'    => "0",
        '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",
        '37'    => "A",
        '38'    => "B",
        '39'    => "C",
        '40'    => "D",
        '41'    => "E",
        '42'    => "F",
        '43'    => "G",
        '44'    => "H",
        '45'    => "I",
        '46'    => "J",
        '47'    => "K",
        '48'    => "L",
        '49'    => "M",
        '50'    => "N",
        '51'    => "O",
        '52'    => "P",
        '53'    => "Q",
        '54'    => "R",
        '55'    => "S",
        '56'    => "T",
        '57'    => "U",
        '58'    => "V",
        '59'    => "W",
        '60'    => "X",
        '61'    => "Y",
        '62'    => "Z",
        '63'    => "!",
        '64'    => "\"",
        '65'    => "�",
        '66'    => "\$",
        '67'    => "^",
        '68'    => "&",
        '69'    => "*",
        '70'    => "(",
        '71'    => ")",
        '72'    => "_",
        '73'    => "+",
        '74'    => "-",
        '75'    => "=",
        '76'    => "`",
        '77'    => ",",
        '78'    => ".",
        '79'    => "/",
        '80'    => "<",
        '81'    => ">",
        '82'    => "?",
        '83'    => ";",
        '84'    => "'",
        '85'    => "#",
        '86'    => ":",
        '87'    => "@",
        '88'    => "~",
        '89'    => "[",
        '90'    => "]",
        '91'    => "{",
        '92'    => "}",
        '93'    => " ",
        '94'    => "%",
    );
    $char_to_num = array(
        '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,
        '1'    => 27,
        '2'    => 28,
        '3'    => 29,
        '4'    => 30,
        '5'    => 31,
        '6'    => 32,
        '7'    => 33,
        '8'    => 34,
        '9'    => 35,
        '0'    => 36,
        'A'    => 37,
        'B'    => 38,
        'C'    => 39,
        'D'    => 40,
        'E'    => 41,
        'F'    => 42,
        'G'    => 43,
        'H'    => 44,
        'I'    => 45,
        'J'    => 46,
        'K'    => 47,
        'L'    => 48,
        'M'    => 49,
        'N'    => 50,
        'O'    => 51,
        'P'    => 52,
        'Q'    => 53,
        'R'    => 54,
        'S'    => 55,
        'T'    => 56,
        'U'    => 57,
        'V'    => 58,
        'W'    => 59,
        'X'    => 60,
        'Y'    => 61,
        'Z'    => 62,
        '!'    => 63,
        '\"'    => 64,
        '�'    => 65,
        '\$'    => 66,
        '^'    => 67,
        '&'    => 68,
        '*'    => 69,
        '('    => 70,
        ')'    => 71,
        '_'    => 72,
        '+'    => 73,
        '-'    => 74,
        '='    => 75,
        '`'    => 76,
        ','    => 77,
        '.'    => 78,
        '/'    => 79,
        '<'    => 80,
        '>'    => 81,
        '?'    => 82,
        ';'    => 83,
        '\''    => 84,
        '#'    => 85,
        ':'    => 86,
        '@'    => 87,
        '~'    => 88,
        '['    => 89,
        ']'    => 90,
        '{'    => 91,
        '}'    => 92,
        ' '    => 93,
        '%'    => 94,
    );
    function lookup($char){
        global $num_to_char;
        return $num_to_char[$char];
    }
    function grimstring_to_nums($string){
        $nums = array();
        $c = 0;
        $total = 0;
        $len = strlen($string);
        while ($c < $len){
            $a = substr($string, $c, 1);
            $num = substr($string, $c+1, $a);
            $nums[] = $num;
            $total += $num;
            $c += $a+1;
        }
        $total = $total / (count($nums) + 1);
        $out = array();
        foreach($nums as $num){
            $out[] = $num - $total;
        }
        return $out;
    }
    function crack_gcrypt($input){
        return implode('', array_map("lookup", grimstring_to_nums($input)));
    }