what function do we use?

[student 123]

Hi,

What function do we use in order to identify between a letter and a number in a string?

[ultifinitus]

You can look at the ascii value.

Or you can use isalpha and those functions.

http://cplusplus.com/reference/clibrary/cctype/

[student 123]

But how do we check if the string contain both number and letter?

[naaokth]

You can check your string character by character using a loop and the cctype as ultifinitus suggested.

If you need to keep your std::string format, you can use :
http://www.cplusplus.com/reference/string/string/data/ or
http://www.cplusplus.com/reference/string/string/c_str/ to work directly with the string as if it was a char*

[student 123]

I am sorry, I am a bit slow in this C++ plus I am new to it.

Can you give me an example on how to use loop for checking the string?

[ultifinitus]

 string mystring = "adjkfal;jeifnawfklesfnr739280728907182903";

 for (int temp = 0; temp < mystring.size(); temp++){
  if (isalpha(mystring[temp]){
   //do whatever you want if it's a letter
  }
 }

[student 123]

Great! It works. Thanks!