C++ By Example 五pdf

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Introducing Arrays

This chapter discusses different types of arrays. You are already familiar with character arrays, which are the only method for storing character strings in the C++ language. A character array isn’t the only kind of array you can use, however. There is an array for every data type in C++. By learning how to process arrays, you greatly improve the power and efficiency of your programs.

This chapter introduces

o Array basics of names, data types, and subscripts

o Initializing an array at declaration time

o Initializing an array during program execution

o Selecting elements from arrays

The sample programs in these next few chapters are the most advanced that you have seen in this book. Arrays are not difficult to use, but their power makes them well-suited to more advanced programming.

Array Basics

Although you have seen arrays used as character strings, you still must have a review of arrays in general. An array is a list of more than one variable having the same name. Not all lists of variables are arrays. The following list of four variables, for example, does not qualify as an array.

sales          bonus_92            first _initial             ctr

This is a list of variables (four of them), but it isn’t an array because each variable has a different name. You might wonder how more than one variable can have the same name; this seems to violate the rules for variables. If two variables have the same name, how can C++ determine which you are referring to when you use that name?

Array variables, or array elements, are differentiated by a subscript, which is a number inside brackets. Suppose you want to store a person’s name in a character array called name . You can dothis with......