ADTs, Data Structures, and Problem Solving with C++ 2nd Edition by Larry Nyhoff

Exercise 8

The following exercises ask you to write functions to do various kinds of string processing. To test these functions you should write driver programs as instructed in Programming Problems 13-23 at the end of this chapter.
Write a function that reads a string of digits, possibly preceded by + or ?, and converts this string to the integer value it represents. Be sure that your function checks that the string is well formed, that is, that it represents a valid integer. ( Hint: Use the functions provided in and.)