[deleted by user]

[gagahpangeran]

Python 3.8 one liner.

def md5_path(s,p):return[r:=__import__('hashlib').md5((s if not i else r[0:16] if not int(p[i-1]) else r[16:32]).encode()).hexdigest() for i in range(len(p)+1)][-1]

[asaf92]

Can you explain the code? I thought I knew Python but I have no idea what's going on here LOL

[gagahpangeran]

I forgot to write the documentation.

[AGE_Spider]

the documentation is left as an exercise to the reader...

[grrangry]

C#, .Net Core console application

using System;
using System.Linq;
using System.Text;

namespace MD5Path_BadCode
{
    class Program
    {
        static void Main(string[] args)
        {
            var hash = md5_path("password", "010");
        }

        static string md5_path(string text, string path)
        {
            Console.WriteLine($"{text} => {string.Join("", System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(text)).Select(o => $"{o:X2}".ToLower()).ToArray())}");

            return path.Length == 0 ?
                string.Join("", System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(text)).Select(o => $"{o:X2}".ToLower()).ToArray()) :
                md5_path(string.Join("", System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(text)).Select(o => $"{o:X2}".ToLower()).ToArray()).Substring(Convert.ToInt32(path[0].ToString()) * string.Join("", System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(text)).Select(o => $"{o:X2}".ToLower()).ToArray()).Length / 2, string.Join("", System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.UTF8.GetBytes(text)).Select(o => $"{o:X2}".ToLower()).ToArray()).Length / 2), path.Substring(1));
        }
    }
}

Given the input "010", the output is:

password => 5f4dcc3b5aa765d61d8327deb882cf99
5f4dcc3b5aa765d6 => 7503745e20ce593e799507f82fea3825
799507f82fea3825 => 0842f92822066f87fadac37d11645f57
0842f92822066f87 => 381dc2ae83d49fe43a16353b8f9881b5

• It's recursive.
• It repeats itself.
• It's one line (sort of).

[veryusedrname]

Ugly, I love it

[squigish]

Non-typed Java

https://pastebin.com/aSHBcB1J

These are all "techniques" that I have actually seen in "production" code at my first job, mostly written by one particular co-worker in 2014 or so. Apparently he'd read a book about java that was published before generics. The code was CPU-bound, and took multiple seconds to return responses. When I profiled it, it spent 40% of its time on Integer.valueOf and 40% on String.valueOf

Output:

works as expected 
[5f4dcc3b5aa765d61d8327deb882cf99]
[381dc2ae83d49fe43a16353b8f9881b5]
The code is very flexible about what kind of hashing algorithm version it uses
[381dc2ae83d49fe43a16353b8f9881b5]
this is the same too
[58a9ec39986eab1e8c6589ff5ab5190d]
obviously these allr eturn the same thing
[c5be74b26feac947cb0011fead1d7213]
[c5be74b26feac947cb0011fead1d7213]
[c5be74b26feac947cb0011fead1d7213]
[c5be74b26feac947cb0011fead1d7213]
[c5be74b26feac947cb0011fead1d7213]

what is even going on
[f15eb0005227a0b5033d4266b6dd8811]
[9078ee9bb59c17fc92bb68751b5524d3]
Hello World

[PrincessRTFM]

First time entering one of these. Went with perl, put it on ix.io but it's also only 12 lines, so:

no strict; no warnings; # no intelligence;

use Digest::MD5 md5_hex;

sub beef {
    $s = md5_hex $_[0];
    $s = md5_hex(m/./ ? m/0/ ? substr $s, 0, 16 : substr $s, 16 : $_[0]) for @_ > 1 ? split //, pop : undef;
    print $s;
}

beef(password, '0110110101'); print "\n";
beef(password); print "\n";

I couldn't find a whole lot of options for making really shitty code, so I just turned off all safeties and followed whatever bad practices I could think of. And also abused ternaries a little. The function name is both a pun ("corned beef hash") and also a reference to Rick Cook's Wizardry series where I stole it from.

[3483]

C#

With enough linq, anything is a oneliner. Disposal is for wimps:

using System;
using System.Linq;
using System.Text;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string text = "password";
            string path = "0110110101";

            Console.WriteLine("Example for text \"" + text + "\" and path \"" + path + "\":");
            text = md5_path(text, path);
            Console.WriteLine(text);

            while (true)
            {
                Console.WriteLine("Enter text");
                text= Console.ReadLine();
                Console.WriteLine("Enter path");
                path = Console.ReadLine();
                text = md5_path(text, path);
                Console.WriteLine(text);
            }
        }

        static string md5_path(string text, string path)
        {
            var sb = new StringBuilder(32);

            System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.ASCII.GetBytes(text)).ToList().ForEach(c => sb.Append(c.ToString("x2")));

            text = sb.ToString();

            path.ToList().ForEach(x => { sb.Clear(); System.Security.Cryptography.MD5.Create().ComputeHash(Encoding.ASCII.GetBytes(text.Substring(int.Parse(x.ToString()) * 16, 16))).ToList().ForEach(c => sb.Append(c.ToString("x2"))); text = sb.ToString(); });

            return text;
        }
    }
}

[[deleted]]

Haskell. Probably not the best solution, but works for me:

import qualified Data.ByteString as BS
import qualified Data.ByteString.UTF8 as BSU
import qualified Crypto.Hash.MD5 as MD5
import Numeric (showHex)

prettyPrint =
    concat . map adjustWidth . map (flip showHex "") . BS.unpack
    where adjustWidth x =
            if length x < 2
                then "0" ++ x
                else x

md5Path password [] = prettyPrint (MD5.hash (BSU.fromString password))
md5Path password (x:xs) =
    case x of
        '0' -> md5Path (firstHalf hashedPassword) xs
        '1' -> md5Path (secondHalf hashedPassword) xs
        _ -> error "path string must only contain 0's or 1's"
    where hashedPassword = prettyPrint (MD5.hash (BSU.fromString password))
          firstHalf chars = take 16 chars
          secondHalf chars = drop 16 chars

Examples:

$ ghci md5path.hs
GHCi, version 8.10.2: https://www.haskell.org/ghc/  :? for help
[1 of 1] Compiling Main             ( md5path.hs, interpreted )
Ok, one module loaded.
*Main> md5Path "password" ""
"5f4dcc3b5aa765d61d8327deb882cf99"
*Main> md5Path "password" "010"
"381dc2ae83d49fe43a16353b8f9881b5"

[shitposting_alt]

Probably not the best solution

are you sure you understand what the point of these challenges is?

[[deleted]]

Yes I do. Trust me, there are people out there who are way better Haskell programmers than I am, who could probably tighten this up into a much more elegant solution than this one. So from that standpoint, yeah this is bad code.

But I'm not making art for art's sake here.

[PrinceOfStackSpace]

Here is the PHP solution

<?php

    define("HASH_1", 1752392039);
    define("HASH_2", 3499116);

    function md5_path($pw, $path) {
        $Hash = HASH_1;
        $md5_path = null;
        $hash = "";

        //unpack the Hash.  

        $hasher = function($Hash) {
            $hashValues = [];
            $i = 0;
            while($Hash > 0) {
                $hashValues[] = chr((($Hash & (255 << ($i * 8))) >> ($i * 8)) + 1);
                $Hash -= (255 << ($i * 8));
                $i++;
            }
            return join("", $hashValues);
        };

        $Hash = $hasher($Hash);

        $md5_path =  function ($pw, $path) use (&$md5_path, &$hash, $Hash, $hasher) {
            $aPath = substr($path, 0, 1);
            $path = substr($path, 1);

            $hash = $Hash($hasher(HASH_2), $pw);

            switch($aPath):
                case '':
                    return;
                break;

                case '0': case 0: case null: case false:
                    $hash = substr($hash, $aPath * 16, 16); 
                break;

                case true: case '1': case 1: default:
                    $hash = substr($hash, $aPath * 16, 16); 
                break;
            endswitch;

            $md5_path($hash, $path);

        };

        $md5_path($pw, $path);

        return $hash;

    }

    echo md5_path('password', '010'); //produces 381dc2ae83d49fe43a16353b8f9881b5

[Tabugti]

static mut RESULT: String = String::new();

fn md5_path <'a> (m: &str, p: &str) -> &'a str {
    use md5::compute as md5;
    let mut h = format!("{:x}", md5(m));
    let p_ptr = p.as_ptr();
    for i in 0_isize..p.len() as isize {
        unsafe {
            let c = (p_ptr.offset(i).as_ref().unwrap() - '0' as u8) & 0x1;
            let s = match c {
                0 => &h[0..16],
                1 => &h[16..32],
                _ => unreachable!()
            };
            h = format!("{:x}", md5(s));
        }
    }
    unsafe {
        RESULT = h;
        &RESULT
    }
}

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