The std::vector
lives in the <vector>
header. So first, we need to add this line of code at the top of the program:
#include <vector>
For review, #include
is a preprocessor directive that tells the compiler to include whatever library that follows. In our case that is the standard vector
library.
And the syntax to create a vector looks like:
std::vector<type> name;
So to define a vector of int
s called calories_today
:
std::vector<int> calories_today;
Inside the angle brackets is the data type of the vector. After the angle brackets is the name of the vector.
Note: The type of the vector (i.e., what data type is stored inside) cannot be changed after the declaration.
Instructions
The Tokyo Subway has different payment options for adults and children. We have declared a double
vector already named subway_adult
.
Declare another double
vector named subway_child
.