shorter way to represent alphabet

Hey everyone i have a piece of code here that i typed out all the letters of the alphabet.

Code:

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string::size_type pos = name.find_first_not_of("qwertyuiopasdfghjklzxcvbnm'QWERTYUIOPASDFGHJKLZXCVBNM " );

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however with the exception of the ' and the trailing space in the set the rest is the alphabet. is there a shorter way to represent this? the reason i ask is because i dont like the long statement in my code. I know there are things like isalpha() etc but i dont know if there is a similar representation for situations like this.

if not then i guess i would have to live with it like this:

Code:

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string::size_type pos = name.find_first_not_of
                        ("qwertyuiopasdfghjklzxcvbnm' QWERTYUIOPASDFGHJKLZXCVBNM" );

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Like

Code:

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const char *alphabet = "qwertyuiopasdfghjklzxcvbnm' "
                      "QWERTYUIOPASDFGHJKLZXCVBNM";

string::size_type pos = name.find_first_not_of( alphabet );

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>is there a shorter way to represent this?
Shorter how? Horizontally? A much better solution would be to read a configuration file with the alphabet so that it isn't hardcoded:

Code:

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string get_alphabet ( string file_name )
{
  ifstream in ( file_name.c_str() );
  string alphabet;

  if ( in ) {
    // Fill the string according to the file format
  }
  else
    throw runtime_error ( "File open failure" );

  return alphabet;
}

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Most likely, all find_first_not_of does is loop through each character until it finds one not in that list. Since the list is long it might make more sense to use your own loop and check for isalpha, '\'' and ' '. If you want to do it in one line make a function that checks for those characters and use it with the find_if algorithm.

hmm. all good ideas, thanks. i just implemented what salem suggested though, it was the easiest to do as i did not want to have to change too much code. there is another part where i would need to input numbers alone, i think i may try to use a loop with find_if and isdigit.
or i might just stringstream the number to an int and then use find_first_not_of again. :D

wait thats the first time i saw pointers with letters. by that i mean i always see pointers pointing to a value like 34 or an address like 3421 or some integer. up to today i have not found any pointer tutorial using anything but int variables. could somebody explain the const char *alphabet to me so that hopefully i would be able to understand it and use it in future.

A string literal (characters between double quotes) are represented in C++ as an array of char. One way to reference an array is through a pointer, and char* is the C method of handling strings. Since a string literal is a constant string that cannot be changed, it has the type if const char* in C++. So if you ever want a constant string "variable" you can use const char* and assign the double-quoted string.

This is also just fine (and the const is good practice but not necessary here):

Code:

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const string alphabet = "qwertyuiopasdfghjklzxcvbnm' "
                      "QWERTYUIOPASDFGHJKLZXCVBNM";

string::size_type pos = name.find_first_not_of( alphabet );

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