arg c (Argument count):-Argument count is int and stores number of command -line arguments passed by the user including the name to a program. if we pass a value to a program ,value of arg c would be 2(one for argument and one for program name).
* The value of arg c should be non negative.
*arg v[ ] (Argument vector):- is array of character pointers listing all the arguments.
*arg v[0] -> it holds the name of the program itself.
*arg v[1] ->it is a pointer to the first command line argument supplied.
*argv[n] ->it is a pointer to the last command line argument supplied.
