Displaying elements of a struct array by using a function [closed] - c++

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So I need to display a table with all of the categories such as housing, transportation, etc along with the other information in each of the arrays that I've initialized. I can't seem tot figure out how to display individual array elements using the "displayTable" function. When I say "cout << housing[0] << " " << utilities[0]" and so on I keep getting a build error. I've tried different syntax as well but I just can't figure it out. It's for an assignment in one of my classes. Any help is much appreciated!
#include <iostream>
#include <iomanip>
using namespace std;
struct Category
{
string category;
double maxAmount;
double amountSpent;
};
void displayTable(Category housing[3], Category utilities[3],
Category transportation[3], Category food[3],
Category entertainment[3], Category miscellaneous[3])
{
cout << setprecision(2)
<< housing[0];
}
int main()
{
int menuChoice;
Category housing = {"Housing", 500.00, 0.00};
Category utilities = {"Utilities", 150.00, 0.00};
Category transportation = {"Transportation", 50.00, 0.00};
Category food = {"Food", 250.00, 0.00};
Category entertainment = {"Entertainment", 150.00, 0.00};
Category miscellaneous = {"Miscellaneous", 50.00, 0.00};
do
{
} while (menuChoice != 3);
return 0;
}

Answer 1

I think you don't study well the array etc. With the string housing[0] you access the first element of an array named housing however in this case there is not array in the code. Maybe you want to create a function that take an element of the type Category and print the value of its field. Something like this:
displayCategory(Category aCategory){
cout<<"Category = "+aCategory.category+"\n"+"maxAmount ="+aCategory.maxAmount+"\n"+"amountSpent = "+aCategory.amountSpent+"\n";
}
Then you maybe want to create an array of Category so instead of declare a variable for every category you could do this:
Category arrayOfCategory[6];
arrayOfCategory[0] = {"Housing", 500.00, 0.00};
arrayOfCategory[1] = {"Utilities", 150.00, 0.00};
arrayOfCategory[2] = {"Transportation", 50.00, 0.00};
arrayOfCategory[3] = {"Food", 250.00, 0.00};
arrayOfCategory[4] = {"Entertainment", 150.00, 0.00};
arrayOfCategory[5] = {"Miscellaneous", 50.00, 0.00};
now if you want a function that print all the category in arrayOfCategory simply using the first function displayCategory we can create this function:
displayTable(Category *anArrayOfCategory, int dimOfTheArray){
for(int i = 0; i < dimOfTheArray; i++)
displayCategory(anArrayOfCategory[i]);
}

Answer 2

void displayTable(Category housing[3], Category utilities[3],
Category transportation[3], Category food[3],
Category entertainment[3], Category miscellaneous[3])
{
std::cout << setprecision(2) << housing[0];
}
housing[0] is of type Category, which you made. How should std::cout know what to print if you give it your own custom type?
You can print the members of your struct one by one like so:
std::cout << setprecision(2) << housing[0].maxAmount;
or implement a custom << operator inside your type:
struct Category
{
std::string category;
double maxAmount;
double amountSpent;
friend std::ostream& operator<< (std::ostream& stream, const Category& category) {
stream << category.maxAmount;
}
};
and then your original code should work fine.
(Obviously you need to add the other members to the output as well, and maybe add some headers/titles, commas etc. for human readability, but the principle should be clear.)

Answer 3

You should treat Category as a struct, not as an array
The simplest way is to access members in the following way
void displayTable(Category housing, Category utilities,
Category transportation, Category food,
Category entertainment, Category miscellaneous)
{
cout << setprecision(2)
<< housing.maxAmount;
}