my program is not accepting 10 digit phone numbers

Clinton Portis commented: keep trying. -1

1. Create a structure for a simple telephone directory system named struct telDirectory{}composed ofchar username[20], long telNum, char address[20].

so starting with your first question,
so about C++ structures fresh your knowledge. http://www.cplusplus.com/doc/tutorial/structures/

and Start to write that structure.

struct tellDirectory
{
 char userName[20];
 long tellNum;
 char address[20];
};

>>(1)Input record values (input records and save it into a text file)
you can do this using the std::cin which is defined in <iostream>
http://www.augustcouncil.com/~tgibson/tutorial/iotips.html
and using cin you can fill your datastructure.

you may define the method like this.

void input_record(tellDirectory& input);

Try I'm there when you get stuck.

My program is not accepting 10 digit phone numbers despite of using arrays

So, correct it...

Be a part of the DaniWeb community

We're a friendly, industry-focused community of developers, IT pros, digital marketers, and technology enthusiasts meeting, networking, learning, and sharing knowledge.