That mysterious independent variable of political calculations, Public Opinion.
This chapter covers arrays and more complex variables.
So far in constructing our building we have named each brick (variable). That is fine for a small number of bricks, but what happens when we want to construct something larger? We would like to point to a stack of bricks and say, “That’s for the left wall. That’s brick 1, brick 2, brick 3. . . .”
Arrays allow us to do something similar with variables. An array is a set of consecutive memory locations used to store data. Each item in the array is called an element. The number of elements in an array is called the dimension of the array. A typical array declaration is:
// List of data to be sorted and averaged int data_list;
data_list to be
an array of the three elements
data_list, which are separate variables.
To reference an element of an array, you use a number called the
subscript (the number inside the
square brackets [ ]). C++ is a funny language and likes to start
counting at 0, so these three elements are numbered 0-2.
Common sense tells you that when you declare
data_list to be three elements long,
data_list would be valid.
Common sense is wrong:
data_list is illegal.
Example 5-1 computes the total and average of five numbers.
#include <iostream> float data; // data to average and ...