递归穷举法

// Java
import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class MD5Util {
  public static final String MD5(String inStr) {
    MessageDigest md5 = null;
    try {
      md5 = MessageDigest.getInstance("MD5");
    } catch (Exception e) {
      System.out.println(e.toString());
      e.printStackTrace();
      return "";
    }
    char[] charArray = inStr.toCharArray();
    byte[] byteArray = new byte[charArray.length];

    for (int i = 0; i < charArray.length; i++)
      byteArray[i] = (byte) charArray[i];

    byte[] md5Bytes = md5.digest(byteArray);

    StringBuffer hexValue = new StringBuffer();

    for (int i = 0; i < md5Bytes.length; i++) {
      int val = ((int) md5Bytes[i]) & 0xff;
      if (val < 16)
        hexValue.append("0");
      hexValue.append(Integer.toHexString(val));
    }

    return hexValue.toString();
  }

  private static final List<Character> chars = Arrays.asList('a', 'b', 'c', 'd', 'e', 'f', 'g', 'h',
      'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A',
      'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
      'U', 'V', 'W', 'X', 'Y', 'Z', '~', '`', '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '-',
      '_', '=', '+', '[', ']', '{', '}', '\\', '|', ';', ':', '\'', '"', ',', '<', '.', '>', '/',
      '?', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9');

  static List<String> strings = new ArrayList<>();

  public static List<String> exhaustive(int count) {
    return exhaustive(count, "");
  }

  public static List<String> exhaustive(int count, String param) {
    if (count == 0) {
      for (Character character : chars) {
        String result = param + character;
        System.out.println(result);
        strings.add(result);
      }
    } else {
      count -= 1;
      for (Character character : chars) {
        exhaustive(count, param + character.toString());
      }
    }

    return strings;
  }

  public static void main(String[] args) {
    for (int i = 0; i < 4; i++) {
      System.out.println(exhaustive(i));
    }
  }

}

 

python：

import md5
import hashlib

def md5_encryption(src):
  src = '123456'
  enc = md5.new()
  enc.update(src)
  print enc.hexdigest()
# md5_encryption('123456')

def hashlib_md5_encryption(src):
  m2 = hashlib.md5()   
  m2.update(src)   
  print m2.hexdigest()
# hashlib_md5_encryption('123456')

_chars = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
          'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
           '~', '`', '!', '@', '#', '$', '%', '^', '&', '*', '(', ')', '-', '_', '=', '+', '[', ']', '{', '}', '\\', '|', ';', ':', '\'',
           '"', ',', '<', '.', '>', '/', '?', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9']


# results = []
def exhaustive(max_digit=0, add_str=''):
  if max_digit == 0:
    for char in _chars:
      result = '%s%s' % (add_str, char)
#       results.append(result)
      print result
  else:
    max_digit -= 1
    for char in _chars:
      exhaustive(max_digit, '%s%s' % (add_str, char));
#   return results
  
if __name__ == '__main__':
  exhaustive(3)

稍微改点理论上就可以无穷列举密码，但是只是理论，电脑根本承受不了，没那么大内存。