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mystring binarytohex(mystring source)
{
  int i;
  char chunk[4];
  char hexchar;
  mystring result;
  result.text[0] = '\0';

  for(i = 0; i < source.length; i++)
  {
    if (i > 0 && i % 4 == 0)
    {
      binaryquadtohexchar(chunk, hexchar);
    }
    chunk[i % 4] = source.text[i];
    if (i == source.length-1)
    {
      binaryquadtohexchar(chunk, hexchar);
    }

  }

}

char binaryquadtohexchar(char * source, char result)
{
  int i;
  char * hexchars[][2] = {
    {"0000", '0'},
    {"0001", '1'},
    {"0010", '2'},
    {"0011", '3'},
    {"0100", '4'},
    {"0101", '5'},
    {"0110", '6'},
    {"0111", '7'},
    {"1000", '8'},
    {"1001", '9'},
    {"1010", 'a'},
    {"1011", 'b'},
    {"1100", 'c'},
    {"1101", 'd'},
    {"1110", 'e'},
    {"1111", 'f'},
  };

  for (i = 0; i <= 15; i++)
  {
    if (strcmp(source, hexchars[i][0]) == 0)
    {
      result = hexchars[i][1];
    }
  }

}